54 files changed, 10217 insertions, 0 deletions
diff --git a/2021/01/input b/2021/01/input
new file mode 100644
index 0000000..7e216a8
--- /dev/null
+++ b/2021/01/input
@@ -0,0 +1,2000 @@
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diff --git a/2021/02/input b/2021/02/input
new file mode 100644
index 0000000..d5c08db
--- /dev/null
+++ b/2021/02/input
@@ -0,0 +1,1000 @@
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diff --git a/2021/02/part1.tl b/2021/02/part1.tl
new file mode 100644
index 0000000..983506a
--- /dev/null
+++ b/2021/02/part1.tl
@@ -0,0 +1,1010 @@
+(defvar x 0)
+(defvar y 0)
+(defvar aim 0)
+
+(defun forward (n) (inc x n))
+(defun down (n) (inc y n))
+(defun up (n) (dec y n))
+
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+(down 1)
+(down 3)
+(down 4)
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+(down 7)
+(forward 4)
+(down 4)
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+(forward 2)
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+(forward 2)
+(down 6)
+(up 8)
+(forward 6)
+(down 2)
+(forward 6)
+(up 8)
+(forward 6)
+(down 9)
+(forward 2)
+(forward 6)
+
+(put-line `x = @x, y = @y, aim = @aim, (* x y) = @(* x y)`)
diff --git a/2021/02/part2.tl b/2021/02/part2.tl
new file mode 100644
index 0000000..8bd775f
--- /dev/null
+++ b/2021/02/part2.tl
@@ -0,0 +1,1016 @@
+(defvar x 0)
+(defvar y 0)
+(defvar aim 0)
+
+(defun forward (n)
+  (inc x n)
+  (inc y (* n aim)))
+
+(defun down (n)
+  (inc aim n))
+
+(defun up (n)
+  (dec aim n))
+
+(forward 9)
+(forward 9)
+(forward 3)
+(down 2)
+(forward 8)
+(down 8)
+(forward 1)
+(down 6)
+(down 9)
+(down 9)
+(forward 1)
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+(forward 3)
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+(down 2)
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+(down 2)
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+(down 1)
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+
+(put-line `x = @x, y = @y, aim = @aim, (* x y) = @(* x y)`)
diff --git a/2021/03/code.tl b/2021/03/code.tl
new file mode 100644
index 0000000..4ffd1f4
--- /dev/null
+++ b/2021/03/code.tl
@@ -0,0 +1,26 @@
+(defun funny-less (left right)
+      (let ((ll (len left))
+            (lr (len right)))
+        (or (< ll lr)
+            (if (eql ll lr)
+              (< (car left) (car right))))))
+
+(defun funny-greater (left right)
+      (let ((ll (len left))
+            (lr (len right)))
+        (or (> ll lr)
+            (if (eql ll lr)
+              (> (car left) (car right))))))
+
+(defun maj-pare-down (list pos)
+      (cdr [find-max [group-by (op ref @1 pos) list] funny-greater]))
+
+(defun min-pare-down (list pos)
+      (cdr [find-min [group-by (op ref @1 pos) list] funny-less]))
+
+(let ((list *2))
+     (each ((i 0..12))
+        (upd list (min-pare-down @1 i)))
+     list)
+
+[apply * (mapcar (op toint @1 2) (flatten results))] ;; results contains two numbers in text form
diff --git a/2021/03/input b/2021/03/input
new file mode 100644
index 0000000..4c5a9e7
--- /dev/null
+++ b/2021/03/input
@@ -0,0 +1,1000 @@
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diff --git a/2021/04/bingo.tl b/2021/04/bingo.tl
new file mode 100644
index 0000000..cd82c47
--- /dev/null
+++ b/2021/04/bingo.tl
@@ -0,0 +1,130 @@
+(defstruct board ()
+  rows)
+
+(defstruct bingo ()
+  numbers
+  boards)
+
+(defun read-bingo (name)
+  (let* ((lines (remqual "" (file-get-lines name)))
+         (numbers [mapcar toint (spl "," (pop lines))])
+         (boards (mapcar (do new board rows @1)
+                         (tuples 5 (mapcar (opip (tok #/\d+/) (mapcar toint))
+                                           lines)))))
+    (new bingo numbers numbers boards boards)))
+
+(defmeth board check (bo)
+  (when-match @(or @(some (* * * * *))
+                   ((* . @nil)
+                    (* . @nil)
+                    (* . @nil)
+                    (* . @nil)
+                    (* . @nil))
+                   ((@nil * . @nil)
+                    (@nil * . @nil)
+                    (@nil * . @nil)
+                    (@nil * . @nil)
+                    (@nil * . @nil))
+                   ((@nil @nil * . @nil)
+                    (@nil @nil * . @nil)
+                    (@nil @nil * . @nil)
+                    (@nil @nil * . @nil)
+                    (@nil @nil * . @nil))
+                   ((@nil @nil @nil * . @nil)
+                    (@nil @nil @nil * . @nil)
+                    (@nil @nil @nil * . @nil)
+                    (@nil @nil @nil * . @nil)
+                    (@nil @nil @nil * . @nil))
+                   ((@nil @nil @nil @nil * . @nil)
+                    (@nil @nil @nil @nil * . @nil)
+                    (@nil @nil @nil @nil * . @nil)
+                    (@nil @nil @nil @nil * . @nil)
+                    (@nil @nil @nil @nil * . @nil)))
+    bo.rows t))
+
+(defmeth board daub (bo num)
+  (upd bo.rows
+    (mapcar (op mapcar (iffi (op eql num) (ret '*)))))
+  bo)
+
+(defmeth board value (bo)
+  (sum bo.rows (op sum @1 [iff numberp use (ret 0)])))
+
+(defmeth bingo solve (bi)
+  (each ((x bi.numbers))
+    (each ((bo bi.boards))
+      (if bo.(daub x).(check)
+        (return-from solve (* x bo.(value)))))))
+
+(defmeth bingo solve-last (bi)
+  (each ((x bi.numbers))
+    (each ((bo bi.boards))
+      (if (and bo.(daub x).(check)
+               (empty (upd bi.boards (remq bo))))
+        (return-from solve-last (* x bo.(value)))))))
+
+(defun tests ()
+  (assert (new board rows '((* * * * *))).(check))
+  (assert (new board rows '((1 2 3 4 5) (* * * * *))).(check))
+  (assert (new board rows '((* 2 3 4 5)
+                            (* 2 3 4 5)
+                            (* 2 3 4 5)
+                            (* 2 3 4 5)
+                            (* 2 3 4 5))).(check))
+  (assert (new board rows '((2 * 3 4 5)
+                            (2 * 3 4 5)
+                            (2 * 3 4 5)
+                            (2 * 3 4 5)
+                            (2 * 3 4 5))).(check))
+  (assert (new board rows '((2 3 * 4 5)
+                            (2 3 * 4 5)
+                            (2 3 * 4 5)
+                            (2 3 * 4 5)
+                            (2 3 * 4 5))).(check))
+  (assert (new board rows '((2 3 4 * 5)
+                            (2 3 4 * 5)
+                            (2 3 4 * 5)
+                            (2 3 4 * 5)
+                            (2 3 4 * 5))).(check))
+  (assert (new board rows '((2 3 4 5 *)
+                            (2 3 4 5 *)
+                            (2 3 4 5 *)
+                            (2 3 4 5 *)
+                            (2 3 4 5 *))).(check))
+  (assert (not (new board rows '((* * 3 * *))).(check)))
+  (assert (not (new board rows '((1 2 3 4 5) (* * * * 3))).(check)))
+  (assert (not (new board rows '((* 2 3 4 5)
+                                 (6 2 3 4 5)
+                                 (* 2 3 4 5)
+                                 (* 2 3 4 5)
+                                 (* 2 3 4 5))).(check)))
+  (assert (not (new board rows '((2 6 3 4 5)
+                                 (2 * 3 4 5)
+                                 (2 * 3 4 5)
+                                 (2 * 3 4 5)
+                                 (2 * 3 4 5))).(check)))
+  (assert (not (new board rows '((2 3 * 4 5)
+                                 (2 3 * 4 5)
+                                 (2 3 * 4 5)
+                                 (2 3 6 4 5)
+                                 (2 3 * 4 5))).(check)))
+  (assert (not (new board rows '((2 3 4 * 5)
+                                 (2 3 4 * 5)
+                                 (2 3 4 6 5)
+                                 (2 3 4 * 5)
+                                 (2 3 4 * 5))).(check)))
+  (assert (not (new board rows '((2 3 4 5 *)
+                                 (2 3 4 5 *)
+                                 (2 3 4 5 *)
+                                 (2 3 4 5 *)
+                                 (2 3 4 5 6))).(check)))
+  (assert (equal (new board rows '((1 2 3 4 5)
+                                   (6 7 8 9 10)
+                                   (11 12 13 14 15))).(daub 8).rows
+                 '((1 2 3 4 5)
+                   (6 7 * 9 10)
+                   (11 12 13 14 15))))
+  (assert (eq (new board rows '((1 * * * *)
+                                (* * * * 2)
+                                (* * 3 * *))).(value)
+              6)))
diff --git a/2021/04/input b/2021/04/input
new file mode 100644
index 0000000..2ad5f8f
--- /dev/null
+++ b/2021/04/input
@@ -0,0 +1,601 @@
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+77 59 66  5 76
+54 13 35 40 82
+51 25 64  6 19
+
+65 36 92 51 74
+55 90 68  9 97
+28 56 35 34 73
+50 10 61 37 30
+79 49 96 18  1
+
+57  8 17 51 19
+86 97 21 84 20
+32 44 33 27 62
+ 3 76 70 58 79
+36 74 75 65 71
+
+24 65 37 29 66
+26 60 49 45 61
+23 22 83 71 10
+46 59 86 40 12
+64 74 27  8 78
+
+63 79 80 54 68
+16 89 60 96 31
+ 6 91 32 37 86
+93 20 61 70 21
+58 88 11 15 39
+
+36 44 75  3 29
+58 32 84 37 48
+76 99 65 91 24
+22 20 42 57 49
+50 85 52  2 54
+
+77 65 38 15 12
+50 53 10 34 40
+87 60  4 68 71
+ 5 35 28 63 66
+11 86  9  8 49
+
+ 3 71 46 10  1
+83 12 52 99 24
+96 87 85 51 33
+11 69 62 34 41
+88 22 89 21 49
+
+55  0 82 40 48
+71 32  3 90 92
+39 69 63 86 60
+51 36 66 12 46
+73 57 58 33 94
diff --git a/2021/05/input b/2021/05/input
new file mode 100644
index 0000000..04fa5cb
--- /dev/null
+++ b/2021/05/input
@@ -0,0 +1,500 @@
+657,934 -> 657,926
+130,34 -> 570,474
+478,716 -> 226,464
+861,110 -> 861,167
+448,831 -> 370,831
+75,738 -> 390,738
+26,880 -> 864,42
+965,658 -> 527,220
+208,381 -> 80,381
+523,475 -> 807,475
+219,69 -> 219,434
+793,538 -> 534,797
+754,602 -> 754,148
+443,327 -> 443,611
+606,395 -> 546,395
+980,56 -> 51,985
+619,325 -> 354,325
+342,123 -> 819,600
+290,533 -> 374,533
+598,77 -> 598,75
+605,302 -> 605,636
+97,981 -> 692,386
+278,779 -> 278,800
+661,377 -> 661,10
+726,108 -> 518,316
+271,883 -> 271,50
+382,271 -> 606,271
+963,358 -> 891,286
+496,880 -> 496,855
+211,142 -> 211,49
+841,866 -> 260,285
+841,849 -> 173,181
+927,326 -> 391,862
+396,558 -> 459,558
+753,183 -> 953,183
+941,698 -> 941,407
+347,612 -> 347,476
+18,340 -> 18,612
+140,299 -> 797,956
+714,907 -> 714,228
+966,155 -> 194,927
+769,674 -> 712,674
+644,675 -> 948,979
+703,872 -> 812,763
+26,629 -> 120,535
+844,738 -> 844,253
+798,133 -> 798,795
+27,318 -> 288,57
+38,545 -> 872,545
+827,351 -> 195,983
+818,45 -> 21,842
+257,559 -> 626,928
+145,925 -> 886,184
+83,618 -> 590,111
+326,243 -> 53,243
+489,278 -> 526,278
+783,693 -> 783,525
+495,636 -> 495,585
+374,716 -> 215,557
+839,536 -> 839,966
+850,468 -> 955,468
+55,799 -> 55,447
+472,722 -> 296,898
+390,731 -> 120,461
+405,493 -> 208,296
+807,42 -> 56,793
+476,327 -> 655,327
+24,965 -> 967,22
+776,211 -> 776,850
+489,20 -> 822,20
+630,740 -> 871,499
+743,493 -> 283,953
+62,429 -> 62,720
+806,270 -> 806,332
+550,154 -> 107,597
+71,713 -> 533,251
+620,575 -> 620,156
+726,829 -> 143,246
+944,553 -> 468,553
+185,582 -> 185,468
+845,266 -> 212,899
+654,97 -> 265,486
+726,609 -> 726,147
+631,76 -> 860,76
+835,24 -> 928,24
+712,719 -> 74,81
+616,478 -> 616,117
+903,226 -> 903,577
+440,699 -> 136,395
+215,705 -> 890,30
+20,24 -> 981,985
+102,144 -> 850,892
+695,967 -> 582,967
+219,284 -> 219,388
+359,833 -> 665,833
+389,55 -> 305,55
+59,32 -> 957,930
+815,198 -> 64,949
+699,540 -> 717,558
+215,682 -> 182,682
+805,489 -> 328,489
+43,546 -> 578,546
+489,181 -> 489,363
+266,391 -> 266,582
+863,368 -> 448,368
+83,236 -> 83,487
+874,875 -> 874,413
+799,90 -> 799,802
+253,29 -> 253,905
+136,446 -> 435,745
+830,534 -> 550,534
+183,785 -> 107,785
+81,517 -> 159,517
+359,941 -> 359,560
+71,546 -> 948,546
+596,811 -> 596,791
+255,960 -> 255,159
+788,15 -> 788,682
+240,55 -> 240,244
+51,423 -> 137,423
+504,418 -> 809,723
+131,842 -> 914,59
+727,790 -> 82,145
+281,509 -> 841,509
+797,807 -> 834,807
+333,499 -> 790,499
+215,328 -> 215,139
+500,898 -> 500,862
+75,217 -> 777,919
+17,264 -> 17,446
+852,755 -> 150,755
+865,186 -> 385,186
+158,192 -> 158,733
+196,261 -> 196,128
+989,960 -> 131,102
+807,393 -> 807,153
+507,579 -> 507,764
+468,76 -> 535,76
+381,357 -> 659,357
+794,277 -> 749,277
+51,152 -> 546,647
+797,959 -> 458,959
+82,156 -> 967,156
+261,624 -> 460,624
+597,53 -> 197,53
+153,507 -> 411,765
+305,717 -> 768,717
+344,954 -> 344,217
+194,432 -> 545,432
+346,46 -> 557,46
+685,599 -> 685,312
+49,719 -> 49,631
+499,668 -> 304,863
+262,405 -> 554,405
+87,64 -> 295,64
+859,675 -> 74,675
+663,776 -> 99,212
+232,189 -> 232,904
+777,276 -> 703,276
+704,492 -> 86,492
+142,736 -> 514,364
+418,611 -> 224,417
+602,571 -> 602,424
+152,603 -> 248,603
+915,673 -> 143,673
+538,32 -> 128,32
+975,885 -> 975,344
+870,511 -> 870,756
+330,798 -> 46,798
+440,195 -> 587,195
+739,237 -> 568,66
+54,838 -> 196,980
+370,556 -> 47,556
+124,575 -> 748,575
+261,283 -> 880,902
+784,91 -> 426,449
+764,670 -> 148,670
+32,51 -> 967,986
+807,906 -> 10,906
+470,488 -> 579,597
+274,649 -> 285,649
+221,540 -> 221,94
+914,957 -> 914,510
+879,825 -> 145,91
+438,833 -> 438,775
+191,844 -> 911,124
+145,763 -> 595,763
+504,81 -> 622,199
+834,206 -> 834,704
+908,308 -> 815,308
+929,567 -> 929,322
+805,50 -> 620,235
+36,409 -> 133,312
+345,375 -> 19,701
+468,948 -> 468,108
+109,547 -> 446,547
+929,916 -> 69,56
+927,857 -> 318,248
+833,948 -> 833,61
+559,787 -> 559,982
+293,825 -> 293,775
+508,744 -> 545,744
+827,713 -> 753,639
+88,775 -> 555,775
+523,812 -> 684,812
+307,142 -> 307,265
+636,40 -> 355,321
+891,875 -> 891,25
+301,423 -> 712,12
+922,187 -> 219,890
+45,447 -> 230,262
+114,568 -> 233,687
+573,398 -> 677,398
+334,101 -> 324,101
+957,277 -> 957,652
+943,834 -> 610,834
+523,632 -> 523,379
+958,361 -> 90,361
+408,824 -> 380,824
+647,314 -> 647,449
+747,83 -> 59,83
+776,104 -> 937,104
+16,984 -> 989,11
+362,581 -> 362,226
+72,962 -> 940,94
+319,877 -> 319,122
+310,206 -> 986,882
+794,877 -> 267,877
+855,58 -> 976,58
+699,971 -> 598,971
+162,556 -> 162,440
+494,859 -> 494,255
+794,210 -> 142,862
+275,510 -> 548,510
+739,592 -> 739,793
+376,985 -> 376,990
+755,264 -> 280,739
+187,34 -> 187,688
+770,827 -> 770,548
+10,68 -> 913,971
+571,427 -> 571,944
+153,211 -> 153,560
+976,972 -> 55,51
+103,611 -> 674,40
+95,972 -> 924,143
+929,94 -> 38,985
+777,330 -> 60,330
+312,430 -> 312,326
+549,433 -> 269,433
+477,267 -> 477,403
+598,375 -> 19,375
+512,799 -> 512,831
+348,700 -> 348,43
+165,97 -> 63,199
+38,835 -> 38,828
+282,334 -> 282,909
+14,891 -> 390,515
+930,657 -> 334,61
+630,341 -> 630,85
+671,464 -> 319,112
+949,340 -> 894,285
+663,916 -> 245,916
+114,395 -> 286,223
+335,804 -> 529,804
+567,338 -> 14,891
+623,705 -> 379,949
+82,864 -> 545,401
+932,128 -> 932,134
+291,294 -> 291,101
+739,765 -> 739,757
+460,94 -> 892,94
+375,673 -> 367,681
+81,831 -> 90,831
+890,402 -> 890,138
+775,547 -> 790,547
+49,927 -> 966,10
+23,116 -> 257,116
+923,75 -> 18,980
+63,986 -> 687,362
+369,844 -> 357,844
+790,188 -> 644,188
+557,282 -> 557,669
+861,173 -> 390,644
+480,529 -> 893,529
+32,960 -> 830,162
+368,725 -> 368,40
+502,600 -> 701,600
+63,977 -> 873,167
+463,518 -> 788,193
+738,406 -> 324,406
+162,931 -> 822,931
+377,487 -> 707,817
+610,319 -> 901,319
+586,658 -> 690,658
+25,288 -> 53,288
+760,602 -> 760,628
+294,62 -> 951,62
+222,773 -> 661,334
+151,483 -> 646,483
+272,852 -> 317,852
+557,906 -> 503,960
+736,445 -> 736,703
+241,376 -> 241,692
+835,41 -> 835,369
+987,743 -> 987,210
+42,700 -> 42,244
+646,136 -> 646,440
+544,751 -> 404,751
+295,651 -> 295,805
+687,878 -> 113,878
+290,142 -> 604,142
+579,920 -> 579,807
+12,985 -> 987,10
+919,940 -> 919,808
+770,143 -> 770,832
+114,76 -> 962,76
+876,882 -> 428,434
+861,139 -> 861,320
+888,59 -> 888,39
+629,823 -> 707,823
+296,598 -> 296,305
+61,54 -> 578,54
+864,58 -> 253,58
+71,861 -> 306,861
+682,181 -> 326,537
+307,418 -> 307,910
+810,251 -> 810,431
+151,836 -> 602,385
+954,987 -> 243,276
+724,272 -> 350,646
+134,295 -> 434,295
+178,235 -> 802,859
+832,688 -> 832,573
+165,334 -> 165,378
+816,26 -> 114,728
+668,192 -> 540,192
+730,341 -> 969,341
+951,169 -> 286,834
+647,115 -> 886,115
+664,288 -> 507,131
+609,362 -> 609,295
+747,479 -> 287,19
+350,967 -> 350,725
+117,383 -> 311,383
+871,124 -> 292,124
+654,271 -> 547,271
+525,773 -> 345,953
+401,670 -> 610,670
+930,196 -> 301,825
+336,37 -> 961,662
+714,212 -> 714,667
+454,848 -> 454,107
+587,390 -> 587,577
+530,437 -> 542,437
+304,229 -> 517,229
+340,571 -> 766,571
+727,941 -> 138,352
+831,325 -> 11,325
+241,294 -> 403,456
+788,658 -> 788,126
+337,360 -> 337,589
+799,402 -> 342,402
+530,820 -> 530,319
+982,27 -> 20,989
+923,936 -> 923,721
+581,395 -> 64,912
+61,509 -> 61,827
+989,580 -> 610,580
+477,592 -> 219,592
+296,775 -> 296,58
+204,12 -> 204,457
+190,171 -> 190,673
+939,200 -> 939,457
+472,282 -> 472,631
+983,331 -> 734,331
+365,609 -> 365,817
+640,698 -> 145,698
+103,618 -> 549,618
+454,319 -> 454,346
+650,815 -> 381,546
+624,603 -> 507,603
+966,445 -> 723,445
+763,129 -> 763,784
+695,145 -> 695,511
+498,84 -> 435,147
+188,716 -> 967,716
+810,446 -> 810,924
+731,483 -> 731,51
+307,783 -> 307,533
+15,956 -> 956,15
+192,210 -> 882,210
+303,173 -> 38,438
+769,952 -> 769,863
+135,781 -> 405,781
+494,436 -> 494,892
+705,394 -> 714,394
+164,37 -> 164,633
+813,232 -> 813,620
+227,906 -> 222,906
+542,432 -> 414,432
+549,858 -> 88,397
+200,101 -> 958,859
+235,565 -> 469,331
+492,871 -> 503,882
+704,398 -> 869,563
+450,736 -> 746,736
+420,706 -> 420,635
+717,493 -> 686,524
+187,554 -> 717,24
+31,851 -> 315,851
+800,230 -> 466,230
+226,324 -> 226,614
+937,927 -> 937,798
+143,26 -> 534,417
+952,344 -> 12,344
+181,361 -> 782,361
+925,906 -> 415,396
+685,944 -> 470,944
+200,627 -> 290,627
+728,285 -> 728,326
+271,864 -> 271,34
+802,558 -> 207,558
+963,26 -> 84,905
+504,60 -> 529,60
+840,292 -> 180,292
+914,272 -> 914,330
+82,107 -> 925,950
+33,245 -> 33,134
+463,663 -> 463,82
+27,305 -> 27,675
+276,894 -> 891,279
+746,325 -> 746,948
+249,657 -> 341,749
+530,848 -> 28,346
+798,617 -> 798,609
+119,767 -> 312,767
+80,18 -> 674,18
+723,374 -> 583,374
+582,985 -> 239,642
+217,765 -> 217,395
+811,159 -> 609,159
+689,896 -> 501,896
+562,881 -> 562,96
+244,621 -> 629,621
+277,379 -> 277,287
+856,153 -> 20,153
+518,228 -> 518,898
+230,789 -> 243,789
+534,335 -> 534,592
+240,790 -> 413,617
+768,615 -> 768,560
+773,101 -> 912,101
+252,571 -> 767,56
+370,595 -> 681,906
+565,176 -> 565,318
+750,465 -> 750,724
+979,130 -> 120,989
+160,153 -> 160,785
+610,222 -> 610,191
+873,124 -> 130,867
+519,593 -> 519,32
+525,947 -> 525,562
+50,292 -> 291,533
+558,927 -> 960,525
+536,694 -> 249,981
+954,896 -> 277,896
+732,202 -> 732,288
+447,989 -> 541,895
+890,754 -> 367,231
+368,89 -> 564,285
+588,100 -> 588,156
+282,313 -> 943,974
+16,792 -> 495,792
+111,591 -> 111,493
+57,713 -> 685,85
+676,632 -> 676,575
+560,708 -> 560,602
+489,288 -> 489,404
+904,515 -> 443,54
+70,977 -> 985,62
+11,119 -> 11,403
+215,859 -> 937,137
+78,469 -> 110,437
+747,605 -> 747,369
+847,598 -> 847,299
+742,695 -> 159,112
+986,370 -> 986,460
+631,900 -> 771,760
+228,406 -> 683,861
+189,639 -> 61,639
+221,650 -> 820,650
+558,569 -> 834,845
+655,533 -> 558,630
+967,921 -> 967,169
+230,308 -> 429,308
+873,762 -> 873,528
+412,151 -> 412,538
+881,587 -> 881,21
+941,45 -> 26,960
+377,126 -> 700,126
diff --git a/2021/05/scratch b/2021/05/scratch
new file mode 100644
index 0000000..d3975a7
--- /dev/null
+++ b/2021/05/scratch
@@ -0,0 +1,15 @@
+525,947 -> 525,562
+
+689,896 -> 501,896
+954,896 -> 277,896
+
+
+
+947                  *
+                     |
+896       *--->*-----+----------*<--------*
+                     |
+562                  *
+
+
+         277  501    525       689       954
diff --git a/2021/05/segs.tl b/2021/05/segs.tl
new file mode 100644
index 0000000..33f06a6
--- /dev/null
+++ b/2021/05/segs.tl
@@ -0,0 +1,201 @@
+(defun read-segs (name)
+  (mapcar (do match `@x0,@y0 -> @x1,@y1` @1
+            (list (tofloat x0) (tofloat y0) (tofloat x1) (tofloat y1)))
+          (file-get-lines name)))
+
+(defun read-int-segs (name)
+  (mapcar (do match `@x0,@y0 -> @x1,@y1` @1
+            (list (toint x0) (toint y0) (toint x1) (toint y1)))
+          (file-get-lines name)))
+
+(defun ccw-from (x0 y0 x1 y1 x2 y2)
+  (let ((dx1 (- x1 x0))
+        (dy1 (- y1 y0))
+        (dx2 (- x2 x0))
+        (dy2 (- y2 y0)))
+    (> (* dx1 dy2) (* dx2 dy1))))
+
+(defun intersect (ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+  (and (neq (ccw-from ax0 ay0 ax1 ay1 bx0 by0)
+            (ccw-from ax0 ay0 ax1 ay1 bx1 by1))
+       (neq (ccw-from bx0 by0 bx1 by1 ax0 ay0)
+            (ccw-from bx0 by0 bx1 by1 ax1 ay1))))
+
+(defun b-proj-a (ax0 ay0 ax1 ay1 bx by)
+  (let* ((adx (- ax1 ax0))
+         (ady (- ay1 ay0))
+         (bdx (- bx ax0))
+         (bdy (- by ay0))
+         (a*b (+ (* adx bdx) (* ady bdy)))
+         (a*a (+ (* adx adx) (* ady ady)))
+         (b/a (/ a*b a*a)))
+    (list (+ ax0 (* b/a adx))
+          (+ ay0 (* b/a ady)))))
+
+(defun isecpoint (ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+  (tree-bind (x0 y0) (b-proj-a ax0 ay0 ax1 ay1 bx0 by0)
+    (tree-bind (x1 y1) (b-proj-a ax0 ay0 ax1 ay1 bx1 by1)
+      (list (+ x0 (/ (- x1 x0) 2))
+            (+ y0 (/ (- y1 y0) 2))))))
+
+(defun collinear (ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+  (and (not (ccw-from ax0 ay0 ax1 ay1 bx0 by0))
+       (not (ccw-from ax0 ay0 ax1 ay1 bx1 by1))
+       (not (ccw-from bx0 by0 bx1 by1 ax0 ay0))
+       (not (ccw-from bx0 by0 bx1 by1 ax1 ay1))
+       (and (or (<= ax0 bx0 ax1) (>= ax0 bx0 ax1)
+                (<= bx0 ax0 bx1) (>= bx0 ax0 bx1)))
+       (and (or (<= ay0 by0 ay1) (>= ay0 by0 ay1)
+                (<= by0 ay0 by1) (>= by0 ay0 by1)))))
+
+(defun dist (x0 y0 x1 y1)
+  (sqrt (+ (square (- x1 x0)) (square (- y1 y0)))))
+
+(defun lap-length (ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+  (let ((a0-between (or (and (<= bx0 ax0 bx1) (<= by0 ay0 by1))
+                        (and (>= bx0 ax0 bx1) (>= by0 ay0 by1))))
+        (a1-between (or (and (<= bx0 ax1 bx1) (<= by0 ay1 by1))
+                        (and (>= bx0 ax1 bx1) (>= by0 ay1 by1))))
+        (b0-between (or (and (<= ax0 bx0 ax1) (<= ay0 by0 ay1))
+                        (and (>= ax0 bx0 ax1) (>= ay0 by0 ay1))))
+        (b1-between (or (and (<= ax0 bx1 ax1) (<= ay0 by1 ay1))
+                        (and (>= ax0 bx1 ax1) (>= ay0 by1 ay1)))))
+    (cond
+      ((and a0-between a1-between) (dist ax0 ay0 ax1 ay1))
+      ((and b0-between b1-between) (dist bx0 by0 bx1 by1))
+      (a0-between (if b0-between
+                    (dist bx0 by0 ax0 ay0)
+                    (dist bx1 by1 ax0 ay0)))
+      (t (if b0-between
+           (dist bx0 by0 ax1 ay1)
+           (dist bx0 by0 ax1 ay1))))))
+
+(defun clip (ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+  (let ((a0-between (or (and (<= bx0 ax0 bx1) (<= by0 ay0 by1))
+                        (and (>= bx0 ax0 bx1) (>= by0 ay0 by1))))
+        (a1-between (or (and (<= bx0 ax1 bx1) (<= by0 ay1 by1))
+                        (and (>= bx0 ax1 bx1) (>= by0 ay1 by1))))
+        (b0-between (or (and (<= ax0 bx0 ax1) (<= ay0 by0 ay1))
+                        (and (>= ax0 bx0 ax1) (>= ay0 by0 ay1))))
+        (b1-between (or (and (<= ax0 bx1 ax1) (<= ay0 by1 ay1))
+                        (and (>= ax0 bx1 ax1) (>= ay0 by1 ay1)))))
+    (assert (or a0-between a1-between b0-between b1-between)
+      "clip: problem with ~s" (list ax0 ay0 ax1 ay1 bx0 by0 bx1 by1))
+    (cond
+      ((and a0-between a1-between) (list ax0 ay0 ax1 ay1))
+      ((and b0-between b1-between) (list bx0 by0 bx1 by1))
+      (a0-between (if b0-between
+                    (list bx0 by0 ax0 ay0)
+                    (list bx1 by1 ax0 ay0)))
+      (t (if b0-between
+           (list bx0 by0 ax1 ay1)
+           (list bx0 by0 ax1 ay1))))))
+
+(defun unify (ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+  (let ((a0-between (or (and (<= bx0 ax0 bx1) (<= by0 ay0 by1))
+                        (and (>= bx0 ax0 bx1) (>= by0 ay0 by1))))
+        (a1-between (or (and (<= bx0 ax1 bx1) (<= by0 ay1 by1))
+                        (and (>= bx0 ax1 bx1) (>= by0 ay1 by1))))
+        (b0-between (or (and (<= ax0 bx0 ax1) (<= ay0 by0 ay1))
+                        (and (>= ax0 bx0 ax1) (>= ay0 by0 ay1))))
+        (b1-between (or (and (<= ax0 bx1 ax1) (<= ay0 by1 ay1))
+                        (and (>= ax0 bx1 ax1) (>= ay0 by1 ay1)))))
+    (cond
+      ((and a0-between a1-between) (list bx0 by0 bx1 by1))
+      ((and b0-between b1-between) (list ax0 ay0 ax1 ay1))
+      (a0-between (if b0-between
+                    (list bx0 by0 ax1 ay1)
+                    (list bx0 by0 ax1 ay1)))
+      (t (if b0-between
+           (list bx1 by1 ax0 ay0)
+           (list bx0 by0 ax0 ay0))))))
+
+(defun rectilinear (x0 y0 x1 y1)
+  (or (= x0 x1) (= y0 y1)))
+
+(defun point-on-segment (x0 y0 x1 y1 px py)
+  (and (or (<= x0 px x1) (<= x1 px x0))
+       (or (<= y0 py y1) (<= y1 py y0))
+       (not (ccw-from x0 y0 x1 y1 px py))
+       (not (ccw-from x1 y1 x0 y0 px py))))
+
+(defun solve-1 (segs)
+  (let (isegs points)
+    (each-match (((@ax0 @ay0 @ax1 @ay1)
+                  (@bx0 @by0 @bx1 @by1))
+                 (comb segs 2))
+      (when (and (rectilinear ax0 ay0 ax1 ay1)
+                 (rectilinear bx0 by0 bx1 by1))
+        (cond
+          ((collinear ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+           (push (clip ax0 ay0 ax1 ay1 bx0 by0 bx1 by1) isegs))
+          ((intersect ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+           (push (isecpoint ax0 ay0 ax1 ay1 bx0 by0 bx1 by1) points)))))
+    (prinl ^(len points 0 ,(len points)))
+    #;(prinl points)
+    (upd points uniq)
+    (prinl ^(len points 1 ,(len points)))
+    #;(prinl points)
+    (set points (append-matches (@(as p (@px @py)) points)
+                  (block nil
+                    (each-match ((@x0 @y0 @x1 @y1) isegs)
+                      (if (point-on-segment x0 y0 x1 y1 px py)
+                        (return)))
+                    (list p))))
+    (prinl ^(len points 2 ,(len points)))
+    #;(prinl points)
+    (prinl isegs)
+    (let ((nl (len isegs))
+          (l 0))
+      (while (neq nl l)
+        (let (nsegs pairs (count 0))
+          (set l nl)
+          (each-match ((@(as l0 (@ax0 @ay0 @ax1 @ay1))
+                        @(as l1 (@bx0 @by0 @bx1 @by1)))
+                       (comb isegs 2))
+            (cond
+              ((collinear ax0 ay0 ax1 ay1 bx0 by0 bx1 by1)
+               (push (list l0 l1) pairs))))
+          (each-match ((@(as l0 (@ax0 @ay0 @ax1 @ay1))
+                        @(as l1 (@bx0 @by0 @bx1 @by1)))
+                       pairs)
+            (if (and (member l0 isegs)
+                     (member l1 isegs))
+              (upd isegs (opip (remq l0)
+                               (remq l1)
+                               (push (unify ax0 ay0 ax1 ay1 bx0 by0 bx1 by1))))))
+          (set nl (len isegs)))))
+    (prinl isegs)
+    (prinl (len isegs))
+    (+ (len points)
+       (len isegs)
+       [sum isegs (lambda-match
+                    (((@x0 @y0 @x1 @y1)) (dist x0 y0 x1 y1)))])))
+
+(defun easy-solve-1 (segs)
+  (let ((ph (hash)))
+    (each-match ((@x0 @y0 @x1 @y1) segs)
+      (cond
+        ((eql x0 x1)
+         (each ((y (range y0 y1)))
+           (inc [ph (list x0 y) 0])))
+        ((eql y0 y1)
+         (each ((x (range x0 x1)))
+           (inc [ph (list x y0) 0])))))
+    [count-if (op < 1) ph cdr]))
+
+(defun easy-solve-2 (segs)
+  (let ((ph (hash)))
+    (each-match ((@x0 @y0 @x1 @y1) segs)
+      (cond
+        ((eql x0 x1)
+         (each ((y (range y0 y1)))
+           (inc [ph (list x0 y) 0])))
+        ((eql y0 y1)
+         (each ((x (range x0 x1)))
+           (inc [ph (list x y0) 0])))
+        ((eql (abs (- x1 x0)) (abs (- y1 y0)))
+         (each ((x (range x0 x1))
+                (y (range y0 y1)))
+           (inc [ph (list x y) 0])))))
+    [count-if (op < 1) ph cdr]))
diff --git a/2021/05/testinput b/2021/05/testinput
new file mode 100644
index 0000000..b258f68
--- /dev/null
+++ b/2021/05/testinput
@@ -0,0 +1,10 @@
+0,9 -> 5,9
+8,0 -> 0,8
+9,4 -> 3,4
+2,2 -> 2,1
+7,0 -> 7,4
+6,4 -> 2,0
+0,9 -> 2,9
+3,4 -> 1,4
+0,0 -> 8,8
+5,5 -> 8,2
diff --git a/2021/06/input b/2021/06/input
new file mode 100644
index 0000000..66ede3c
--- /dev/null
+++ b/2021/06/input
@@ -0,0 +1 @@
+3,5,2,5,4,3,2,2,3,5,2,3,2,2,2,2,3,5,3,5,5,2,2,3,4,2,3,5,5,3,3,5,2,4,5,4,3,5,3,2,5,4,1,1,1,5,1,4,1,4,3,5,2,3,2,2,2,5,2,1,2,2,2,2,3,4,5,2,5,4,1,3,1,5,5,5,3,5,3,1,5,4,2,5,3,3,5,5,5,3,2,2,1,1,3,2,1,2,2,4,3,4,1,3,4,1,2,2,4,1,3,1,4,3,3,1,2,3,1,3,4,1,1,2,5,1,2,1,2,4,1,3,2,1,1,2,4,3,5,1,3,2,1,3,2,3,4,5,5,4,1,3,4,1,2,3,5,2,3,5,2,1,1,5,5,4,4,4,5,3,3,2,5,4,4,1,5,1,5,5,5,2,2,1,2,4,5,1,2,1,4,5,4,2,4,3,2,5,2,2,1,4,3,5,4,2,1,1,5,1,4,5,1,2,5,5,1,4,1,1,4,5,2,5,3,1,4,5,2,1,3,1,3,3,5,5,1,4,1,3,2,2,3,5,4,3,2,5,1,1,1,2,2,5,3,4,2,1,3,2,5,3,2,2,3,5,2,1,4,5,4,4,5,5,3,3,5,4,5,5,4,3,5,3,5,3,1,3,2,2,1,4,4,5,2,2,4,2,1,4
diff --git a/2021/06/sim.tl b/2021/06/sim.tl
new file mode 100644
index 0000000..69d9ac2
--- /dev/null
+++ b/2021/06/sim.tl
@@ -0,0 +1,31 @@
+(defun read-fish (name)
+  (flow
+    (file-get-string name)
+    (tok #/\d+/)
+    (mapcar toint)))
+
+(defun sim-naive (input n)
+  (while (plusp (pdec n))
+    (upd input (mappend [iff zerop (ret '(6 8)) [chain pred list]])))
+  (len input))
+
+(defun sim (input n)
+  (let ((phase (vector 9 0)))
+    (each ((i input))
+      (inc [phase i]))
+    (while (plusp (pdec n))
+      (rotate [phase 0] [phase 1] [phase 2]
+              [phase 3] [phase 4] [phase 5]
+              [phase 6] [phase 7] [phase 8])
+      (inc [phase 6] [phase 8]))
+    (sum phase)))
+
+(defun sim2 (input n)
+  (let ((phase (vector 9 0)))
+    (each ((i input))
+      (inc [phase i]))
+    (while (plusp (pdec n))
+      (pset [phase 8] [phase 0]
+            [phase 0..8] [phase 1..9])
+      (inc [phase 6] [phase 8]))
+    (sum phase)))
diff --git a/2021/06/testinput b/2021/06/testinput
new file mode 100644
index 0000000..55129f1
--- /dev/null
+++ b/2021/06/testinput
@@ -0,0 +1 @@
+3,4,3,1,2
diff --git a/2021/07/calc.tl b/2021/07/calc.tl
new file mode 100644
index 0000000..b6dac9c
--- /dev/null
+++ b/2021/07/calc.tl
@@ -0,0 +1,22 @@
+(defun read-crab (name)
+  (flow
+    (file-get-string name)
+    (tok #/\d+/)
+    (mapcar toint)))
+
+(defun calc (input)
+  (let* ((mn (find-min input))
+         (mx (find-max input))
+         (rg (range mn mx))
+         (cost (op sum input (op abs (- @1 @@1)))))
+    [cost (find-min rg : cost)]))
+
+(defun calc2 (input)
+  (let* ((mn (find-min input))
+         (mx (find-max input))
+         (rg (range mn mx))
+         (cost (op sum input (opip (- @@1) abs (* @1 (succ @1)) (trunc @1 2))
+                 #;(lambda (x)
+                               (let ((n (abs (- x @1))))
+                                 (trunc (* n (succ n)) 2))))))
+    [cost (find-min rg : cost)]))
diff --git a/2021/07/input b/2021/07/input
new file mode 100644
index 0000000..4ac01fd
--- /dev/null
+++ b/2021/07/input
@@ -0,0 +1 @@
+1101,1,29,67,1102,0,1,65,1008,65,35,66,1005,66,28,1,67,65,20,4,0,1001,65,1,65,1106,0,8,99,35,67,101,99,105,32,110,39,101,115,116,32,112,97,115,32,117,110,101,32,105,110,116,99,111,100,101,32,112,114,111,103,114,97,109,10,601,578,981,315,530,525,671,1501,616,214,724,1247,543,58,183,282,242,54,90,130,1788,360,1719,710,1165,1476,29,744,164,293,1360,274,47,119,16,387,134,547,72,48,77,416,863,39,65,144,500,678,430,160,1689,550,753,1478,480,56,583,85,206,93,335,990,174,276,1119,52,308,470,563,387,897,21,85,720,983,178,383,134,299,722,57,391,489,768,232,646,1312,1316,31,57,927,176,531,421,1162,369,934,7,172,237,340,169,261,1371,1351,1268,72,58,375,1570,1238,55,513,403,1462,141,263,419,1316,852,251,39,358,209,204,439,150,1667,344,205,1299,1226,992,967,536,1160,1503,1154,1323,486,1079,329,823,506,1252,387,28,69,649,296,233,62,219,344,464,1284,291,234,47,949,1126,935,1367,1450,1431,379,344,478,731,648,77,184,927,211,262,728,1093,381,140,239,332,1436,78,665,1486,601,1444,364,1057,753,488,127,1001,350,1016,357,638,309,40,333,136,655,779,821,414,275,140,149,185,445,1169,476,196,907,1570,193,161,43,204,1489,1125,1024,101,17,592,1378,338,1625,3,269,1568,254,803,25,776,109,52,291,1595,255,739,34,768,378,632,4,181,373,162,562,74,85,160,16,47,38,266,1610,9,7,1398,358,287,450,188,1390,37,98,80,685,1645,50,55,16,542,20,443,848,49,808,76,233,69,110,471,73,408,638,89,861,280,1062,75,314,808,237,96,401,57,48,1306,115,1164,1533,5,1032,1314,66,630,96,496,116,1558,438,13,182,1360,802,101,327,370,444,335,812,430,900,1259,1117,318,118,433,501,401,101,582,27,454,981,776,14,26,163,384,1652,87,788,474,588,155,845,207,33,200,622,840,1360,432,11,525,86,296,481,200,529,95,924,431,40,846,220,285,14,66,755,111,647,643,1201,81,483,555,125,426,1499,29,115,48,39,92,316,434,217,218,116,9,33,496,358,1106,736,1181,1153,117,20,1719,1113,1620,26,581,407,114,1559,6,1918,964,909,340,630,817,473,111,1485,434,262,1702,651,11,182,1043,1904,633,336,252,677,1238,637,1008,82,327,171,185,19,141,395,1209,53,798,836,1378,598,262,298,265,287,85,21,249,848,162,89,1050,108,34,41,25,291,918,28,1234,139,351,867,146,79,995,1173,635,24,31,81,214,1114,155,1256,159,206,586,426,452,650,1653,47,42,264,240,500,864,893,1308,1249,853,286,62,592,102,77,1082,91,120,625,211,978,319,655,200,152,86,396,52,308,1479,38,41,53,179,648,216,41,641,659,1556,226,1421,291,33,1461,1095,529,309,1100,314,1695,505,1200,150,946,53,124,139,1506,52,33,463,613,33,1264,386,678,563,564,318,273,912,60,31,150,1321,133,1333,302,1243,49,421,808,1399,555,195,611,268,39,1302,1154,92,664,117,92,124,332,561,1436,865,198,71,271,909,40,1185,664,251,422,306,122,814,158,1676,122,217,312,952,845,104,572,1796,392,651,176,714,44,757,111,56,489,333,738,369,304,1239,105,297,277,674,213,938,2,681,336,171,1252,166,88,489,273,260,565,231,319,1085,650,211,510,12,511,325,46,107,980,1136,16,95,308,935,514,469,20,44,209,345,467,1310,500,75,594,166,199,741,193,28,52,106,1437,366,575,1200,609,678,534,573,723,325,8,386,268,690,321,186,375,2,104,657,1341,601,175,0,745,146,508,180,426,811,7,215,300,86,25,372,233,900,276,1625,808,1941,510,234,813,131,334,58,783,992,236,244,174,609,1581,1767,204,187,208,1340,347,803,146,299,140,142,339,60,118,300,809,276,413,267,946,77,154,466,425,193,187,852,674,2,17,1006,1007,166,195,137,97,41,407,65,1072,20,789,311,1227,20,132,1536,995,194,506,635,115,1500,529,93,72,950,208,944,1177,476,207,1228,5,974,226,225,290,690,581,218,401,49,361,1408,242,254,24,313,441,635,126,513,994,299,1722,52,1123,44,1332,628,534,789,298,692,45,596,1583,77,15,38,1293,1181,1498,772,148,297,49,692,87,594,49,148,170,54,1079,7,468,847,336,421,34,1108,406,892,689,245,298,85,1187,1142,286,310,207,34,660,549,39,1172,97,1,750,47,0,77,1632,135,54,18,22,1292,230,1031,11,225,820,461,1208,108,1443,274,1134,41,287,166,274,1032,585,1491,75,549,1231,1314,443,212,395,386,698,58,644,395,81,905,366,233,716,656,799,643,1011,173,790,360,269,930,13,606,488,387,1206,51
diff --git a/2021/07/testinput b/2021/07/testinput
new file mode 100644
index 0000000..18bd32a
--- /dev/null
+++ b/2021/07/testinput
@@ -0,0 +1 @@
+16,1,2,0,4,2,7,1,2,14
diff --git a/2021/08/input b/2021/08/input
new file mode 100644
index 0000000..ce56799
--- /dev/null
+++ b/2021/08/input
@@ -0,0 +1,200 @@
+fgcae ebafc cabdef eg abecfg abgfed feg gafdc bceg ebgcadf | defagbc faecg cfdag gecb
+eagd cad fgadbc aefdcg dcebfg fcegd cbeaf ad dbgfeca defca | cfdeg gdcabf fcgde afgced
+gfdeca aeb eb fbdag eafdc adfbe cefdab bdaegcf efbc ecadgb | eb dbafe eab faecd
+facbdge efdg gcafd daegc caegb aecfdb ade ed gafbdc dgfeac | de abcdef faedcg dfgca
+dcaegbf bc dcgeab cbgad cebg cdfaeb fbadg acdge cefdga cdb | gdcfae gbec gdace cgadfe
+ceagfbd fbaeg fadge fbegad abgecf dafcg ed edab ged dfcbeg | gebfa de gbafec ed
+acedbf adfbg cgafedb geac cgb befcgd bcgaf bfgace cg bfeac | bcdfeg fecba cafgeb bgdfa
+egadc cea ac agbcedf cgab bgcade fbcaed eadfbg fegdc ebdag | fdecabg fcged cdbage efgdab
+cbfge gdc cdea efdag dc cdfeg gfbcad gcdeaf cdeagbf egfadb | dfcge egcfd fcdbag dc
+gaedb fbced gcdbef cge gc decgb dcbgfea cgfb cgdfea fbcade | fdegbac fecbd ecg degba
+geaf bcfedg agbcd bfeagd dgfbe cbdaef beacdfg abe agebd ea | fbecdg geaf gebfad adgbc
+bed afgebd adecf bafgedc dbca cfegb becdf fabdce bd gcfdea | gfdaeb ebfgad dbefc cbda
+gacfebd ag bedfca agbfde egfcab dfga degab fbade bag bdecg | dgaf abcfed agb bfecag
+afebg afdeg gcbe acebdf cfbage cafeb gab decgabf bg gcfdba | gb caebf abgef acfebd
+efdab fabdgce gcbfa eg gacbfe beg ecag beafg dfabcg bgecfd | bge fgdcbe gcfdba ebdaf
+aecbd bdagef gd bfega aefgcbd gfde gfdcab dbg edgba febagc | dg dagfbc dgfe eabdgf
+gdfba egfacbd gdcefa baf gcba fdagcb dgfac ab dcfeba ebgdf | dcfag bfa gafcd cbag
+afbe bdagc cedfb defcab ebfdgac gfedbc cbfad af adgcfe adf | dafbc dfbac fdcegb gadcb
+fcgedb ca fdcage cagdbef ceab acedfb fdbce cafdb cda afgbd | ac dcafb efgdac ebcfda
+fbad gbcda dcefgb cfeadg dgbcaf bcafdeg ad gcabe adc dfbcg | gbcdef bcfdg cgbfd bfadgc
+afcgeb bedag bdecafg agb bedfga fdagce bg bgfd dfgea cdabe | badge cagdfe efdag afegbd
+gfed dcaef ge bafdce daceg acebfg cefadg egc ecdabfg gacdb | bcgad bcegaf agecd degcafb
+deacb adcge ab acb fbdce faedbgc fgadec gabd deabgc ecbfag | dfbec ab cbagfe bcfgae
+gcabfde ecf cbdeg bacgf fedg ecfgb gfedcb fcaedb cebdag fe | dbcegf bcgdfe gfde defg
+daefb bfg gedafb fabge dbafec cfega bdga cgbdfe gb gbacedf | aecfg bcedaf begdcf dgba
+bagce bf bdacfeg efbg fcb cefab gbfadc cafebg ecdfa bacdge | fegb cegba bagce efbg
+becag cfeg cefgbad fbace gfeacb acdegb bef ef adbcf fdabge | ef bdfac cbegad gbeac
+egb afcbe fbaeg eabgfdc gcab gb gfdea fgbecd bcdafe gafbec | fcdgeb edcgbfa gbe fgeba
+dga caebd ecdag cegfd abdfce dafbge ecbgda bcdgefa ga agbc | afdbec ecfdab gdaec gad
+fc gbdefc cfe ebdaf fcbeda gbafde edacg bfcdgae dacef cabf | decgfba cdbefg cf ecdabf
+febgd dafgbc caed cgd ceadgf fbecga dcgfe aegfc gbedfca cd | dgfeb fgced dcafebg agdfce
+ecdafgb bgade bgd fabd gbaef bd egadbf ceadg cfbgea dgbfec | edagc bdage bfda dbgae
+cgeba aefgcd dfceagb dc ced facbed cdfb dbaec adfeb fgedba | fbdea bgcae efbda fcdeag
+caegbf dcfga afcedgb afgdcb fcedag ab edbcg dbfa gdcab abg | bag cbdag agb ab
+gadfecb befc fgdbea cf fedagc fac bcgfa agbfe adgcb feagcb | gbcda cgbad bcgfa cf
+dae aefcb dgabec dacfg afebdc ebfd afecgb aedcf fbcagde ed | ecabfgd bedf bcadef egdacfb
+abcf fcega fdgce fegbda eafdcgb ac gabecd gbfae beagfc eca | edbgca edbfga cae gface
+bgedcf afcdbg ag gcbaef fcedgab afgdb cfgbd befda acdg agf | fdbga ceadbfg egfbac fag
+bad edafc bdeg abcgde ecafgbd gfadcb bgaec db edcba geafcb | cdafe fdcabg cdfageb dbge
+geb bgcf agfcde gb befag gfbcae defab gabdec eacfg gabecfd | afbedgc gceabf abgef egacf
+fdeac acg cfegda cbeadf fegdbca ag acefg adge bfdgca gbcfe | gecdaf efgca cgbafd cfgeb
+begdf bdfgc ebcf adfcg cdegbf dgeafb cbg cb bfeagdc gbdcea | acgedb fagdbe bgfde dfgac
+afcgdb aedc bedgf egafcd afdge gecaf fcgebda gda da ceabfg | gedbf gacfe adg agdef
+bdeafg acgebdf dgcfa fa cafe dgfbc gaf edagfc cgabde agedc | fadbge bdgfcea dgcefa cgeda
+gacfbde defag cbgef gbca efadcb afcbeg cgbdfe ba eba gefab | fegab abe ebfcgd fbgae
+gfbdec fbcade cabdegf ebdg bfd dcfgb cadgf gebcf db fcabge | eacdgfb bdge ebdg ecafdb
+egcfba fdcae fcdaeb gcfdae fabd ba cdeab fcdbaeg eba decbg | cabed facbed cbade dfcea
+agdfe acfdeg fcdbeg dgf gdaec df cadf ceagbfd abgfe gbdaec | bgcdef abfge gbefcd df
+dgebf afgdb bfa fcbade af dcafgb agcf gcbda dabgecf gadecb | dbcga abcdge fadgbce eagcbd
+dbcga bea egacdf dageb be efbd abgfce gadfe fcbegad aebfdg | eba be bdage bedga
+gcbd egbdafc fgc fbgedc gc aedbfg cefgb fedbg cfaegd efabc | bface egfbc bgdacfe gc
+fdgae dc ced gbcd gbcefd decfba becfg ecfabg cgfde gbcadfe | edbcfg cd cafgbe cdegbf
+geadcf efg gadef fg fecad acbgfe dagecbf dcgf gadbe afbdce | edafcg bgcfade gfdc abedg
+edcba ecgdb aedbcf aebf dabfc fdacge badgfc ae ead gfcbade | gcebdaf degbc ebfadc efdcba
+caedbg dbgec dcbf ecgdbf cgdef dgf bgaedcf egacf afebgd fd | cdfbeg ecfbgda gcbfed cbgedf
+bdag acdeb ecgdb egbcfa fcdbega gb dbecag cbdafe ebg gdcef | bedgc abdfcge efagcb cdgef
+bfade bfdga dfbgec cagbfd dfgacbe gba gacf ag gdcbf abgedc | cfag abdcge ebafd abefd
+agcdef bcfda bdgca aebdfcg eagdc gb dbg gbea cedagb bfgdec | dfabgec eafdgc acdge gdecab
+ebacdfg cgbfad egdbc bdgfa daef bae gabed febadg ae gacbef | fagdb daebgf fgdab bea
+dcgbf cbedf degc bgc fcgdbea fbadg cfdgbe gc efacgb fdbace | edfcb cfeabg cg edbacf
+bcdagfe dfacb cbfdge bgcdf fdgeac acd agbd acbef da dcgfba | cbgdf dgab ad gbdcaf
+edgfbca gbe be ceba bdaecg gefcd dbagc egbadf dcegb dfgabc | gcfde gfceabd gfbcad eagfdb
+dfcbg fcdga efgb gecbfd gecbda dfbgaec bedfc dgb bfadce bg | dbcgf bfge dacgf dfgcbe
+cga ebdgaf bfdag cbgfe bfadgc gbfeadc ac cagfb cdba cgadef | bfdag agedcf aegcbfd gcfab
+gcead gfdbec cbdge gabfce eb dfgcba ecfdgab befd dgcbf ebg | cdgae fbdegc bcdge gcdfb
+da ebgfda fcdeagb acgbfe gedba dbegc agdecf dae bafeg bfda | gdafec fegba edfbga aed
+fbagec gdfba bcg gebcfd cbafg bcdfgea ebac cefag faedcg bc | gfbac baegcfd fabegc dgeacbf
+dfbeag fabdg fdbe abdeg eb dcega gcefba cfdbag dgcfbae geb | cgbafd bdef dcage eb
+abdcfe gba dagf cagbefd fdbea bfega ag dafbge dcbeag gfceb | afbcde ecgfb dfbega bdgeca
+dg dge gdbc cfdae bcgae cbdage abgfde cfedagb cdgae eacgbf | eabgc bgeac bcdg cagbe
+bfd dgaeb gcabde fd bfgce dgfa dbefg gadbfce dbafge fabcde | edfcba efbcg df bdf
+gcbfd agbecd fedc edcbfg fdb eadfbg bcfag fd gedcb gbacdef | fgbac bdagfec gfbdaec aegbdc
+cgbdfe ce acedg adcfeg bcfegad fcea ceg abdeg afbdcg fcgda | ecg aefdcg dacge ec
+egbdfca efacb agcdbe cbaed bdafgc dfaecg debg bd bda agced | geadbc efbca gabfdc bd
+edcfb bfgecd ecabfd eca abcd fgeab fedcag abfedgc ac bfeca | bgfae eca cdgfeb bfaec
+cadef cebdga ebd bacdfe dagfec dbfa fcebg ecbgfad db fdecb | befcd acgdeb abdf dbfa
+gbfecda bfd cdagb fbdacg fgdbec gbaf cbadf aefdc eadcgb bf | adcgb dfbca agbf dafcb
+abedg acbgf fd gaefcb cagbdef cdaf dcbfeg bdagf dgcbfa bfd | gbadcef df fadgb gabcdf
+fbgadc dbcfg dcega cgdfe cfedbg caefgb ef gef gfaebcd fedb | fcedg febd gbcdfa cdgfab
+bg adgb fcaedbg cgfda fcbae bcg dfacge fgcdba decgfb bcagf | cgafb dbfcage bdgcfe dbga
+ed afbdg acefb aecbfg cfdabeg gedfcb fcdabe ecda def ebdfa | gbafd gedfcb dfegcb dfgba
+gcdfae efgdb abdfcg fde gdabf dbcegfa fedgab efab ef ebdcg | eafb gbfda gacedf cbdge
+edagfc gfaecbd bgced cbegfd cb gefdc badgfc bdc efbc adegb | dgbec cegafd dcbgef dgecb
+gedcab beg eg cafgb fbegc gdfe bdgfec gabcedf bdafce bcdfe | gcefb afcbed ge gdfe
+fdbagc cdgefab edacf ceba ea cfbaed ecfdg abfegd adfbc eda | ea beadfc abcgdef ecdgf
+fbc gfbacd fecda cbdfa dbgf dceabg gbcdfea efbgac cdabg bf | gbdf agbced gaedbc gfdb
+aegcb bfgecd fbegad fcagdbe dfgce fcbd gdeacf fb bgf bgfce | bgafedc gcdaef dgfcbe eadgcf
+def dbce agdfeb ed fdgbcea dgcfb aegfc dfgbac gecfd cdfgbe | cdfegb ed cdgfaeb ebdc
+ecbfad afdb eagbfc caebgdf edfcb dgfec cgdbae bd bcafe bdc | bfacegd fbdcae dbc bgfdcea
+dfgba eg cfbead gde bfedgc dceab cabfdge gdbae aecg aedgcb | egd adebg gde debcfa
+cadfb egfb afgbc adbegc ecgadf ecagb fga ecfgab bgacfde fg | afcbg cgfba gf dacbge
+cegbf dec efcdg facdge dfae dcbafge ed adgfc fdbagc cgaebd | dce gbcfe afcdgbe dcgabf
+cfabe fa eabgfc cgaf fba gfbce dcfbge edbgcfa efbadg acebd | cfebga bfa fedcagb abfce
+acdfb dbagf afcebgd beag afgedb gfdea gbd fgdcbe gb cdeagf | dafge gafed gfacde gb
+gdfeac dfgce ebfadcg edagc dacf baegdc fd gdf egcfb dabgef | degfbac cfdeg daebgf cdeagb
+fcgabe ebcd ecfdg dabcgf gfecabd cfd ebcfg dc bcfegd adefg | agedf cd bcefg dc
+cbaeg bcfea fb feb gfaceb gdfbec dagbec gfab deacf bgcaedf | acbfge bf afgb efb
+egdba cadgfbe efadbg cg begc bfgdca caegd abcegd dcg acdfe | fbegcad bceg gcd cdgebaf
+agbcd dafcgb cfdg ceadb fdgeba eafbcg gfdab gbc bgdcafe cg | gfadcbe fbagd decba gc
+gfbec adgc dge egdcfa abgfde abgdfce dg eacfdb fdaec gdfce | fecgd gd fgcbe acdef
+fdbceg bfedc af fegcad cbdag daf efab dabcef fbeadgc cbfad | fcabd cbfad gcfdbe gadbc
+ebgac fabdeg bedca cg aegdcfb geacbf ceg efgba facg fbedcg | gecdfb aebfg fagc ceg
+eagb dcgeb ba abd cbeagd cdgafb fecbdga fgedcb dacfe dacbe | bdfeacg cadgbf bgedfc fcdae
+dbac cfgae cbfgde ba bga gcfbad dcfebga gcdbf feagbd cgbaf | cgafb fagbdc dcfbg afgebd
+adbgfe fgb egdafc cbafd dfegbc edgafbc egfcd cegb gfcdb gb | bg fdacge efcadg egdfba
+agfbe cgaefdb gbdf edagb afg cdgafe gfedab fg egcdba fabec | fcbdega fag agf agf
+cae edabfc cdfega ca cfba gadeb fdecb ecagfbd cbgdef acdeb | facdeb fgecad bfadce efcgbad
+facb dbfec dceabf efgcd cb aecfbgd dgfbae eafdb ebdagc bcd | bfedc cdegab cbdfe adefb
+fecbga badgc dga bfgadec dg geacb cgedba dfebag gcde fcabd | decg gda baceg gd
+gecbd gcbdfea cbfg bg bge egbcdf dcbef beafdc cdeag bfgeda | agcde dceag gfabde beg
+gefba gacfbe facdeg cg cgab gfc efbdcag cfgeb cefbd afegbd | gfc afbge dafegb aebcgf
+egd aebfgd gefc ge gedbfca bdcfe dfcegb gecdb edbacf cdbag | dacbg edcfbg bcdfe ge
+df ebdga gcdefa cfbd bgdfa afgcb dfeagbc bfacgd fgd facebg | gaebd gecbaf fdcb dfbag
+fag cegfdab cadebg dabcgf abefg eafc ecafgb ebacg fbdge fa | ebfag dbcgfae gbecad fdbgac
+gecbd gefa gfc fabdcg bfaecd ecgafbd fg befgc efabc gecbfa | gfae gcf egbdafc edgbc
+bfgae fcebag fdbe fd fedag adgfbc fdbgea ecagd agcbfed fad | fgabe dfeb ebfd gefba
+ecdgfb afge bdage ebcda eg abdgef fgadb gabcfd dge bcdagef | gdebfa eg agfbdec afeg
+dbc acefd cegadbf fbcde afcb fdcaeg bc acdbge febdac debfg | ceafd caefd gfbaced dcb
+fecgb fgacd gdcefba de gbafce febd gecfd edc fecdbg ecbgda | becdfg ed becgad gcdeba
+agfdbe fbac bcd edacfb bgecfd cb cdeba cfgdeab acged edfab | cb dbc adbce bdfae
+dgacef bdfa ecgbf ab fegba dgafe efdbgca abg acebdg afbdge | gefda ecgafd ecfbg begcad
+gbfcea bgfa afdebc aegdcb af bgcdfea bgeac gecdf afc fgace | bfgecad fca afc abfg
+cfe dgcfe fdagcb gebdc egfa gbcdefa dcebfa fe agdfc fgaedc | dfgac fe fce fcdbega
+fecgab gcbdef cbaefgd dfgbe dgcfe eb bfe dbfga edbc acfegd | fbdeg fdgeca agefbc egcfd
+aecd bac dfacbe cafdb ac gefcab gfcdbe fcbde gbdaf cbdegaf | gcdbefa fbgcae ecad fagecb
+eagbf cagedf geafdbc fdgbce adefb aecfd adcb deb faecbd bd | ebd deabf fadcge cdagfe
+gadefcb bfcga eadcgb egdbfc deag ecg edabc acedbf eg abgce | gdea bagce gce gce
+agcfe bec gecab gbeda facb dbfgec fcegab gfacde gfdaceb cb | cb cefdgb cadefgb bc
+fdgb df egabcf fegda cedga fegab efdbac def cgdefba gafedb | facdbe bafceg agedf fdebga
+fdaecg dbcafg abfgec dc caefg cedg aecfd abdgfce eadbf fcd | cgefab gbfacd fbegac fabecg
+dfecabg bcfeag gdafce dagbfc cdefb dca gafbc dbag da bcadf | dca bagfce cbfda cdagbf
+dabfgec febadg gbcdae gfbe adebf ef cabdf edfgca ebgda eaf | gfacbed abgced egdfca egfb
+cfdea dc fdagebc fegcbd agdc gcfade fcabe cfd efdgba gfead | bdfcge agdc dgefa cfd
+gbfca febadcg bc bdegcf beca begaf gabedf cgfbae cgfad cbg | bcg dcaefgb dfgceb afebdg
+cg cgbf bedcg fcagde adefbcg efdgcb ebacd cgd edbfg egdafb | cfgedb bgcf acegdf cfgb
+bfad adcgbe faceg fagbdc df afdgc efcbdag dfbegc gfd badcg | gfd abgcd fgd abfd
+bcadgf cgdfb adgcb gf gafc dcfeabg bdagce dgf dfbega cebdf | adcbfg gfca fdcbe gfac
+daebf fcabgde bgdcef gab ga edbcga afcg ebfga aefbgc egbcf | ebcfg ebcgfa fcgebd agcf
+gedab fg afgecb cfgd feg cfabed befdc fgdcbe gdceafb befgd | ecafbg ecfbd febdc gf
+gcbadf ce gfcdb fec feabd gbecdf dbcfage febdc agcdfe egbc | bafed gcbe gefcbd egcb
+cbdfg gbcafd feb gaecf gcbfe gfbdae be fcgabde bdgcef becd | abgedf gdfebc aedgfb fbe
+edacgbf fbdae edgac bg gab bagdec dagfce fadbgc cebg bgdea | aedgb bg cebg adcge
+bda gbfea gedcab gfbceda bgdfa bfcdg febcdg bagcfd cfad da | dbecag bgfdc gdbfa facd
+ceabd dabfe acgde bc fbca cgbfde febgda dfecagb ebafdc bdc | cbdae dbfea fgdceb gbfedc
+acg fadbgce cfgdeb dbgce efdca ag dbga cagbef egacd cdgbea | gdecabf gcbfea ecbdg gac
+dfgacb ged egfdab efcgbda gcefbd debga ebadc ge aegf gfdab | cdfgab cdafgb bfcgda ge
+gdbeca bcfde eafg cefbgad dgafcb ge degfb adefbg dgfba bge | bdfeg begdf ebfadg eabdfgc
+cfbdgae gbaec bagfcd gfcba dcaeg bacfeg dbeacf bec efgb eb | ceb egcab cagfb dgcae
+fdcagb gdaecb fcadg bcdgaef gd dfcea gbcaf aecgfb cgd dgbf | gfadc gfdb badgfc gbfca
+bcafed defgcab fgcb cfbae cagde agebfc gbcae gbe gadefb gb | bg gfcaeb bg aedgc
+bcfadeg gbfd eacfbd gdafe afebg bafegd geafcd gebca fb bfa | agdefc eafbdg fgead gedaf
+fcgeabd dgeaf ebgfad gceafb geadc ac aec ebcdg cafd adgefc | gbfadec egcbd acfd dgabef
+eac fbdgec ea eadb cbaeg agfdecb eafdgc dcgbe bcfga adcbeg | aec abde eac ea
+cedb gcadbe ed edgfbac fbega abdge gacdb fdacgb dcefag aed | cdagb gbcafd gdefac gedafc
+cae agfbec ae begcd feab fadgbc ecfadg ecabg cdgbefa cabfg | ecgba afcgb efba dgeafc
+fecgabd badf efadg abedfg fea fdgceb fedgb aebfgc af gdcae | ebfgca fae fea af
+bgedac gbfae dcbefg acbf fb gaedf cagedbf aebgc gebfca fgb | aedgf fdgea bgfae bfdgeac
+bagcfe eadcb gb facegdb bgc fdcag efbcad beadgc bgadc ebgd | gbc fbcage becad gbfcae
+cagde gbca dcgbea gc efcad dbgfea dfgecb caedbfg adgbe cdg | gc egdfbc bcga cg
+efgcbd aebgcd dfe eadfb abged abdcefg bacfd ef bdfaeg faeg | fgae cgdaeb adefb afcbd
+cgbfea gcbda gefdcb eadf febag bdf fd febgad fadbegc bgadf | gebcfd fgdbea dfb dbf
+dg cdgfe gecfad dfbce bgefda fgd eafcg efcbag dgac bcdagfe | afdebg gfd aecgf gfcea
+edfga cgefda gcdbe fbae ab egdabf cfgbda deabg bad adefcgb | ebadg agdeb fbae gbdae
+gbdcfa gbade ebgac ecbfa adfgbec badecf bgc gcef fbgace gc | gc fcge gacefdb ebgca
+acefgd ebgaf egfda egcd bgfaecd dgcfa ed abcefd efd abdgcf | def ebgaf fed befcda
+fecag cag cfagbd agfcbde fabec eabg fdcge cgbfea fadebc ag | cfgbda dfgbeca efdcg dfgcaeb
+bgecfda ecdag dgfcbe bdgac adbgf afgdbe bfac gdcabf cbd bc | bc acbgefd fagcdb fcba
+ba efacg cfbgde cfdbg bacgf bgfdea abf bcad cfbeadg bgcfad | bcdgef fdgaeb ab cagfe
+cbdaf bafdgc eacbd fd dcf fcabg bcdfeg bedgcfa dgfa agbecf | dfga bgfac df agdf
+edcabf cadbf bgfdcea bgcfad bgcde dfg fg bdfgc cgadfe abfg | adfecg gfbcd acgdfeb cbgdaf
+badgfc dg bagcde bceda dbcfea beafg debag adg fcbadeg edgc | gebda dcagbf dceba egfab
+edcf dacfbg dbcefag fbd df bdegfc ebdagc bgfea begcd bfedg | dgebc cbgde dgfbac bdf
+bdcfg acegfb acebfd fdcag egadcf da daf cgeaf edag bafcegd | gdcaf fgaec bafdec fdaecb
+cagefd fde gdfba fcgaedb abefd ef dafbeg ebfg afcbgd ebdca | egdbfa bceda dfabg bdace
+fcgb gcdae bg gfadeb cbfegd fcabed bdg gcdbe fdcbe adbefcg | dgb gfbdec befdc gfbc
+fabde bgfde bgecda cedgb gf cabfdeg ebfdgc fgbeac fcdg gfb | fgbde efdgb edgbc afedb
+ebacf cedfab fde eabfd fd baecgf bagde agdebfc dfcb egfadc | ebfdgac acdegf abdefc ebfad
+gdcb cd cfgae cgbedf fbegd efgdc fadcbe gfeacdb dce dfagbe | gbcd cde gacfe gefdbc
+geb afedgb bfegca bgade eg dgef gadbc eafdb afebdcg fcbead | cagbd defcba dbafec geafcb
+fgbdc gbfade gba gefa dbafg cbadge bfgecda ga edbafc dfabe | afbdeg dgfba bgdfa dcfgb
+agef badce ef febad cabfdg gdfab cbgeafd egfbdc defgba fbe | abefd geaf gafdbe ebcad
+gd gad bfdg gecba fedabcg fcgeda aedfbc adebf agbdfe dgeab | ebcdaf agd gcfbdae egacb
+cedbfa ba cgbfa abf dfegac cafeg gabe befgca ebdfcag cbfdg | fab aegcf faecbd fdcebga
+daefg febdga aegfdbc efgdca eafb bge eb agbdec febgd gbdfc | gbcfd edbfg egb bacegd
+fbdecg bdafec cfaeb gedac def dceaf abfd fd gfecba gfdaecb | ebfac bdfa gbcdef fd
+fcbga cbdfeag bafgce fdacg dc fcd fcgbad fadge efcdgb cdab | gaefcb bafegcd acdb abcgf
+ecgabd acgdf abge ae bcfead fgdaceb ead daegc bcdefg gcbed | egba gaecd cgadbe gdbce
+aegfbc gf afebdc agebdfc ebcdf feg dcefg bdfg dcgea bgedcf | edbfcg fdgb bdgafce febgcd
+dcg bcdefa dbfceg fdeacg acbeg bfeagcd cfdae dg dfag agdec | dfcgea dg egdca edagc
+agcfeb fagbed fdbceg bag gebfd afgd agbfcde acbed ag badeg | cbdea fcedgb gfebac abcegf
+adbegfc fgdace cadge afcg ebdfca ebgad eac bfgdce cgefd ca | acged fcedg ebagd dgacefb
+gfeadb gfeab bcfa agebcfd aebgfc fecgbd efc fc gadec egcfa | fgbace fc debgcf afgceb
+bacg ab cfgbd bfadge acfed fgdecb agedcbf fcabgd bfa dbafc | gfdcb cbga abcg afecbdg
+ge beagc cfgabd bgaced bgcda fbadgec age ecdagf egbd fcbae | aeg gedbac cadfeg fbgcda
+dgbafe abfdgec gdf fd agebcf gadec dfcgba befd edfga aebfg | abcgefd dagec dfg df
+edfcga bcegd baeg cbgdae agdbc gce acgdebf eg gfadbc cefbd | dcbeg bgedc cedbg edcbg
+adfbe dg cagef dfgb gdbeca aefdg gda edcbaf fdgeba gdecbfa | cdabef eafbd bafcegd dg
+cd edcbfg dbage fcaebdg facd bgcfea afbedc afbec dbc adecb | adegb bcefag abegd cbgedf
+gdcbf da ecgbfda adc adgb bagcfd dfbcea egfac dfbceg gdacf | gdba cfdbg adbfec fcaeg
+bcg bc gdcbae dbca abfgde gdeba ebfacdg egcba faceg dgfbce | geadb badecg ecbfgd baecg
diff --git a/2021/08/one.tl b/2021/08/one.tl
new file mode 100644
index 0000000..13ed27d
--- /dev/null
+++ b/2021/08/one.tl
@@ -0,0 +1,7 @@
+(defun solve (: (name "input"))
+  (flow
+    (file-get-lines name)
+    (mapcar (do match `@a | @b` @1 b))
+    (mapcar (opip (spl " ") (mapcar len)))
+    (flatten)
+    (count-if (op meql @1 2 4 3 7))))
diff --git a/2021/08/two.tl b/2021/08/two.tl
new file mode 100644
index 0000000..f436779
--- /dev/null
+++ b/2021/08/two.tl
@@ -0,0 +1,42 @@
+(defstruct entry ()
+  digs
+  value)
+
+(defun read-input (: (name "input"))
+  (flet ((str-to-syms (str)
+           (flow str
+             (spl " ")
+             (mapcar (opip (tuples 1)
+                           (mapcar intern-fb))))))
+    (flow
+      (file-get-lines name)
+      (mapcar (do match `@a | @b` @1
+                (new entry
+                     digs (str-to-syms a)
+                     value (str-to-syms b)))))))
+
+(defun match-dig (syms)
+  (match-case syms
+    ((a b c e f g)   0)
+    ((c f)           1)
+    ((a c d e g)     2)
+    ((a c d f g)     3)
+    ((b c d f)       4)
+    ((a b d f g)     5)
+    ((a b d e f g)   6)
+    ((a c f)         7)
+    ((a b c d e f g) 8)
+    ((a b c d f g)   9)))
+
+(defmeth entry solve (e)
+  (each ((p (perm '(a b c d e f g))))
+    (let* ((map (relate '(a b c d e f g) p))
+           (interp (mapcar (opip (mapcar map) sort) e.digs))
+           (digs (remq nil [mapcar match-dig interp])))
+      (if (eql 10 (len digs))
+        (return (flow e.value
+                  (mapcar (opip (mapcar map) sort match-dig))
+                  (poly 10)))))))
+
+(defun solve (input)
+  (sum input .(solve)))
diff --git a/2021/09/code.tl b/2021/09/code.tl
new file mode 100644
index 0000000..a0e223e
--- /dev/null
+++ b/2021/09/code.tl
@@ -0,0 +1,59 @@
+(defstruct board ()
+  w h a
+
+  (:method lambda (me x y)
+    (if (or (minusp x)
+            (minusp y)
+            (<= me.w x)
+            (<= me.h y))
+      #\9
+      [[me.a y] x]))
+
+  (:method lambda-set (me x y nv)
+    (set [[me.a y] x] nv)))
+
+(defun read-input (: (name "input"))
+  (flow (file-get-lines name)
+    vec-list
+    (new board
+         h (len @1)
+         w (len (first @1))
+         a @1)))
+
+;;-----------------------------------------------------------------------------
+
+(defun solve-one (bo)
+  (sum-each-prod ((y 0..bo.h)
+                  (x 0..bo.w))
+    (let ((c [bo x y])
+          (u [bo x (pred y)])
+          (d [bo x (succ y)])
+          (l [bo (pred x) y])
+          (r [bo (succ x) y]))
+      (if (and (< c u) (< c d) (< c l) (< c r))
+        (+ 1 (chr-digit c))
+        0))))
+
+;;-----------------------------------------------------------------------------
+
+(defmeth board basin-size (bo x y)
+  (caseq [bo x y]
+    ((#\9 #\space) 0)
+    (t (set [bo x y] #\space)
+       (+ 1
+          bo.(basin-size x (pred y))
+          bo.(basin-size x (succ y))
+          bo.(basin-size (pred x) y)
+          bo.(basin-size (succ x) y)))))
+
+(defun solve-two (bo)
+  (flow
+    (build
+      (each-prod ((y 0..bo.h)
+                  (x 0..bo.w))
+        (let* ((bs bo.(basin-size x y)))
+          (if (plusp bs)
+            (add bs)))))
+    sort
+    (nthlast 3)
+    prod))
diff --git a/2021/09/input b/2021/09/input
new file mode 100644
index 0000000..d304456
--- /dev/null
+++ b/2021/09/input
@@ -0,0 +1,100 @@
+6543656799989432399987654342234567896545789323988432145689954545656789543434567987757565678995432345
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diff --git a/2021/10/code.tl b/2021/10/code.tl
new file mode 100644
index 0000000..4e020cb
--- /dev/null
+++ b/2021/10/code.tl
@@ -0,0 +1,35 @@
+(defun corrupt (str)
+  (if-match (@pos . @len) (search-str-tree str '("(]" "(}" "(>"
+                                                 "[)" "[}" "[>"
+                                                 "{)" "{]" "{>"
+                                                 "<)" "<]" "<}"))
+    pos))
+
+(defun reduxe (str)
+  (while-match (@pos . @len) (search-str-tree str '("()" "[]" "{}" "<>"))
+    (del [str pos..(ssucc pos)]))
+  str)
+
+(defun solve-part-one (: (name "input"))
+  (with-stream (s (open-file name))
+    (let ((score 0))
+      (whilet ((line (get-line s)))
+        (let ((rline (reduxe line)))
+          (iflet ((pos (corrupt rline)))
+            (inc score
+                 (ecaseq [rline (succ pos)]
+                   (#\) 3)
+                   (#\] 57)
+                   (#\} 1197)
+                   (#\> 25137))))))
+      score)))
+
+(defun solve-part-two (: (name "input"))
+  (flow
+    (file-get-lines name)
+    (mapcar reduxe)
+    (remove-if [orf corrupt empty])
+    (mapcar (opip (mapcar (relate "([{<" #(1 2 3 4)))
+                  (rpoly 5)))
+    (sort)
+    [callf ref use [chain len (lop trunc 2)]]))
diff --git a/2021/10/input b/2021/10/input
new file mode 100644
index 0000000..3095eaa
--- /dev/null
+++ b/2021/10/input
@@ -0,0 +1,102 @@
+((((<([<{(<(<[<><>>[{}()]>{{()[]}<[][]>}){{(()<>)(<>())}}>{<(([]())({}<>))[<{}()>{{}{}}]>}){{<
+<{<[([{<{{<{[({}())[<>()]]([{}()]{{}[]})}{([[]]<{}[]>){<<>[]><<>[]>}}>}}{[{[{[[]{}]<[][]>>{[<
+[([<[(({(<[<[(<><>)([]())][((){})<<>[]>]>{([<>()]<<>[]>)({{}<>})}][{(<()()>{<><>}){[<>[]][<
+[<[[[{{<{{((<[[][]][[]<>]><({}[])>){{[<>()]{{}{}}}<(()())[<>[]]}}){[(({}{}))](<(<>)>{(<>())(<>[])})}}<<[<<<><
+{{{[{[[{{{{{<<{}<>>{{}[]}>[{<>()}<<>{}>]}<{<<>{}>{[]<>}}({<>()}<(){}>)>}[[(([]<>)<{}()>)]{{[<>{}](<><>)}{([
+{{<[([<[({(<{([][])[{}{}]>([{}<>](<><>))><[[<>{}]]<{<><>}{{}()}>>)<[[([]{})]([<>[]]({}[]))]({(
+({(([[<<([(([([]())<{}<>>](<()[]>[[]{}])){{{()[]}<<><>>}})<{((<><>)[()[]]]}>])><{<(([{()[]}])[{[{}<>]({
+{[<{(([{[([(<[(){}]<()[]>>[<{}<>>[[]<>]>)]{{({[]}({}()))<<{}<>>{<>{}}>}[({<>[]}[[]<>])([{}[]](<>[]))]})
+[({<({([<{<<({()()}<[]{}>)<<<>()>[<>()])>[(<{}<>>[[]()])<(()()){[]<>}>]>}[([<<{}<>>({}{})>[<[]<>><<>()
+[([(<[([<[([[((){})<()[]>]([{}[]](<>()))]){<[<<>()>(<>{})][[<><>]]>({([][]){<>[]}}[{{}}<()()>])}
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+[((((<[(([[<{{()[]}{<>()}}{<[]{}>{<>[]}}>[[{<>{}}([]{})]]][([<()<>><{}{}>]<<[]()>{{}()}>)]](<{[[
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+[{({[[[[<{(<[{()}<[]<>>]{([])}>[(<()<>>({}<>))[({})]]){<<[[]]{<>{}}>{({}{})[<>()]}><{{()<>}({}[])
+[[([[{(((<{(({(){}}[[]{}])[{{}()}[{}()]])[<<{}[]>((){})>]}>{<<[<(){}>](<[]<>>{{}<>})>>}))[{{(({[<><>][
+{({{[{{<<<<<((<>())<[]<>>)<<()<>>({}[])>>>(<{[[]{}]{<>[]}}(<()<>>{[]<>})>({{[][]}([]())}{({}{})[[]
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+({<[<<{<[[<{(<{}()><(){}>)<<[][]>{{}{}}>}[<[{}<>][<>[]]>({()()}<[][]>)]>]}({(<(<<>[]>[<>()])><
+[({((({[<{<{{[<>{}]({}{})}}><<({()[]}{(){}})([[][]]<<>[]>)>{<{()}(<>)>}>}><{<(<<{}>(()[])>)
+<{<([<{{[(<({<{}[]><[][]>}<{(){}}<[]>>)<<({}{})>[{(){}}<[]()>]>>{<{{[]<>)[[]()]}{(<>[])[()<>]}>[
+[<<{(<[{[{<{<[(){}]><{<>}<[]()>>}{<[<>{}](<>>>}>[[<{()()}[()[]]>{[{}()]<{}[]>}]]}]}]>{{<[<[<<{()[]}[[]()]>
+<(<{<[[{<<((<(<>[])(<>{})><[[][]]({}[])>))>(<{<<<>[]>{{}[]}>[({}<>)[()<>]]}>)>}]]>}{{(<<<[
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+<{[<<({[(<({([()][{}()])}([{{}{}}([]<>)]{{{}}<{}()>})){<{{{}}(()[])}([[]<>]{()[]})><<(<>[]
+{({[{[(<<[<{[<<>()>[[]<>>](<<>()>[<>()])}<<[()[]]<<>{}>>{{(){}}[[][]]}>>]>>[(({({([]{})<<>{}>}<{()[]}{[]{}}
+([(({[{<{{[<{<{}{}>(<>{})}>([<{}[]><<><>>]{(()<>){<><>}})]}[([<[()[]]{<><>}><{[]}{{}[])>]([({}<>)<()<>>]))
+{<<<[([(<<<{<{{}[]}{<>()}><<{}()><(){}>>}>[<<[<><>]<()()>><<(){}>{[]<>}>)(<{(){}}({}{})>{[
+(({({[<[(([[(({}[]){<>()})]]<([([]())<{}[]>]){{{{}[]}{<>()}}([[][]](<>{}))}>)[<[{<{}()>{{}<>}}]<<
+{{(({{<((<<({[(){}]<[]()>}(<{}()>[<>()]))[{{{}<>}[<>()]}[{[]}{()()}]]>][(<<<[]<>>{{}()}>(<{}{}>{<>{
+({([{<{{{[{({{[]()}<[]{}>})[{<<>()>{[]}}<({}{})({}<>)>]}<{[[[]<>][{}()]][[()<>]([]<>)]}({[<>[]]<{}<>>}<
+[[(<[[({<[{({<{}()>[()[]]}{{[]()}{[][]}})[(({}<>)<<><>>)[([]<>)<{}[]>]]}]>>[{<<(<[[]<>](()[])>[<{}><[]()>
+(<<<<[{<{({<(<{}<>>)>{({[]{}}<<>{}>)<[{}<>]<[]()>>}}){{{{([]<>){(){}}}[{[]<>}[[]{})]}[({(){}
+({[{{[{[[<([[<{}()>[[][]]]{((){}){()<>}}](([{}[]][[][]])[([]())]))>]]{<<<<([{}[]])<([])[{}{}
+({(((({{{[[[[{<><>}]<[<><>][(){}]>]{{(<>()){<>[]}}{<()<>>{<>}}}]]}}<[<<((<{}<>><<>[]>){<<><>>{()
+{{<<{{[<<[[<[<{}>[{}<>]]<<<><>>([]())>>(<(<>())(<>{})>(({}{})(<><>)))]<{{{[]{}}[<>{}]}(<(){}>[()()]
+[<(<<{(([{{(((()()){<>()}){[[]()]})((<{}()>[<><>])[({}[])([]<>)])}{([(<>[])<{}<>>]{[()()][{}()]}){[{<>()}<<>
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+<<[[(((({<({{([][]){<>()}}}<{(()())<{}()>}{[[][]]<<>()>}>)>})[{{<{[{<><>}[(){}]]((()[])(<><>))}>([<
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+{{<[{([{{<{([<[]<>>[<>{}]][({}()><<>()>])[<[()[]](()())><[[]]<[]()>>]}{[([<>[]])[<[]{}>]]{{(<><>){{}<>}}(
+[(<({<[{<({[[{[]<>}[[][]]]<{[]()}<[]()>>]<[[[][]]{[]<>}][<[]<>>{[]()}]>}[<<(<>{})[{}{}]>[{{}()}[()()]]><[(
+<([[<(({<{[{{<()[]><{}()>}{{{}<>}}}([{{}[]}<{}<>>]{<[]<>>({}[])})]}>((([{<[]<>>{<>[])}(<<>[]
+({{<[[([{<{{<[<>{}](()<>)><(()())>}[[<{}[]><<>()}]<{()<>}[()()]>]}>{<<([<>()]([]{}))((<>())[[][]])>
+([((([[[{{<((<<><>>{[]})<(<><>)<()<>>>){([[]{}][[][]])<<{}<>>{{}<>}>}>{<<[(){}][()()]>[<[]()><
+[<<[[({<<[[<<<()<>>[()[]]><(()())>>(((()[])[(){}])((<>[]){{}[]>))]<<{[[]()][()]}>{(<{}<>>(<><>))<[<>()][
+{{{[([(({{{(([{}[]](()<>))({{}{}})){[({}())(<>[])]}}{<(([][])[<>()])([(){}][{}[]])>[[[[]()]]({<>()}<<>>)]}
+{<(<(([<[<<[[({}[])<<><>>]]({<[]()>}({[]()}<[]()>))><<(((){})(<>[]))>({{<>[]}({}<>)}{<{}()>(()())})>>([<{{
+[<{[[<[({{{<{{[]{}}<[]{}>}{<<><>>}>}[{[([][])<{}()>]({[]<>}[()()])}[([{}[]][[]<>])]]}}<<{[([{}(
+{[([(<{{{([{<[<><>]<<>{}>>[<{}[]>[[]<>]]}])<({[<[][]><[]<>>][<<><>><{}()>]})>}(<{<[(()[])<()
+{((((<{[[[{([(()[])[<>()]]){[{{}()}]}}{{{({}[]){[][]}}[<[]()>]}}]]{[[<({<><>}(<>[]))[({}{})<()()>]>]{{[
+[(({[[<<{<[[(({}{}){{}{}}>[[[][]]<{}<>>]][{{<>()}{[][]}}]]>[[[<<{}[]>>[[<>[]][<>{}]]]{{{{}(
+[([[[[{((<([{[{}{}]([]())}{[()()][{}<>]}])<({{{}{}}<()()>}<([]{})[(){}]>)<({{}{}}<<>[]>)<[<><>][(){}]>>>>[[
+[{{<[{<((([{{<[][]>{<>[]}}({<><>}<<><>>)}<<<{}{}>{[]{}}>{[[]<>]({})}>][<<{{}}(<>())>{{[][]}<[]>}>
+[(([({<(<{[{<{<>{}}><[()()]<()[]>>}{((()())<<><>>)[<{}<>>[<>()]]}]}{{{(<{}{}><<>[]>){{{}}[(){}]}}}{[<{[]{}}>{
+{[[{<[(<<[({({{}{}}[{}<>])[(<>{})<<><>>]}(([{}{}](()()))(<[]>[<>[]])))<({<[]()>}[[<><>]<()
+<[({({<[((<[<({}<>)({}())>]>[({{[]}<{}()>})((<[][]>((){}))[<(){}><()()>])])([[([{}{}]<(){}>)](<<{}[]>{{}<>}>)
+<<<[<{[[<{[<<([]<>}[{}{}]>>{[(()()){()<>}][<<>{}>{{}{}}]}][[<[[]<>]{<>}><{[]<>}{{}{}}>]<[{()
+([({{[({{{({<[[]]<{}[]>>}{{<[]()]<<><>>}{[()<>]([]())}}){{[<<><>><<>{}>]<(<><>)([]{})>}}}(
+{[[[({{({[((<[[])(<>{})>{[[]<>]<()>})[[<[]<>>[()()]][{[]<>}<<>[]>]])[<{<{}{}>([]())}{[<>{}]}>]]}[((<
+[<(<<<{{((<<({[]{}}([]{})><({}{})>><({<>{}}<()[]>)({[]()}[{}()])>>(([[()[]]<<>[]>](<<>()>({}<>)))<<([
+{[[{{<<[[[[[([()()}(<>[]))]((<<><>>[[]{}])(<{}[]>[{}()]))]{<{{{}<>}}({<>()}{()()})>{{<{}()><{}<>>}}}]]<({<
+<<<[[{(<{({([{<><>}<[][]>]<([]())[{}]>)})<<[<{[]()}({}{})>](<{{}[]}[()[]]>(<[]<>><<>()>)))>}
+([([((([(<({<[[]<>][()()]>})[[<<<>><<>[]>>({()()}([][]))][<({}[])<<>[]>>{{{}()}{[]{}}}]]><<[<{(){
+{[([{{<{{[{{{<<>{}>}}<[(())(<>{})]{({}<>)[{}[]>}>}{<([[]()]([][]))[[<>[]]<()[]>]>}]({{{[[]{}]{{}()}}}}([[
+{[<[(<<<[<{([(<>[])<{}()>]{[[]{}]<[]<>>})}>]{{[(<{<><>}[{}()]>{[[]{}][{}{}]}){[([]<>)({}())]{{(){}}({
+((({<{<[[[({<[[]()]{()()}><[<>()][{}[]]>}<(<{}[]>)((<><>)<{}{}>)>)]]{((<<[{}{}][[]()]>(([]<>)[[]{}])><[{[
+{<[<<([<<<{([{<>[]}[()[]]]([{}<>]<[]<>>))<[{<>[]}[{}]]>}[[<[<><>](<>{})>{[()<>)[{}()]}](<((){})([]<>)>)]>
+{[((<[<((<<<{{{}<>}(<>[])}({<><>}(<>{}))>[[<(){}>((){})]((()[]){<>()})]>[<{[[]{}][{}()]}({(){}}<{}
+[{[<{<(([[([(<[]()>((){}))[([]{})[<>{}]]]{<{{}()}(<>{})>})<{(<{}{}>((){}))<{<>[]}<<>()>>}>]({<([{}<>]{<>(
+<{(<([<<{([<{([]{})<[]()>}<{[][]}({}[])>>{(<<>{}>){[()[]]<()()>}}]<[<(<>())><{()()}[()<>]>]>){<{[<(){}><
+(<([([<{<{[<(({}[])((){}))[[{}()](<>())]>][[{[[]()]<()()>]]<<{[]()}>{[{}<>]<[]()>}>]}<<([{{}<>}<()
+[({(({[[[[({{[{}{}]}{(()())[<>[]]}}<{<<>()>(<>[])}(([]){<>{}})>)<<{{[]}[<>()]}{{<>[]}<[]()>})>]]]]})[<[
+<((([[{({(<[<{{}<>>[[]()]><<[][]>[{}()]>][<<{}[]><{}<>>>{[{}()]{<>{}}}]><[{<(){}>{()()}}<(<>{
+[{<{(<{[((<{<{{}[]}({}{})>{({}[])[<>[]]}}{({[]()}){[{}()]<()>}}><<([[]]{<><>}){[[]()](<>{})}>{(<(){}>{[]
+<<([{(<<(([{[{<><>}<{}<>>][[()<>]]}([(()[])[[]()]}<<<>{}>{(){}}>)])[(<<{()()}><[()[]]{<>()}>><(([]{})
+[(<([<{<{{((<((){})<[]{}>>({()[]}({}<>))))}([<[(<>())[{}[]]]((<>[])[{}[]])>[[[(){}]{<>{}}]]])}[{({(<()()){{}
+{({<(<(<{{(({{<>[]}{<>[]}}[{{}}<<>>]))<<[<()[]><()[]>]<({}{})<<>[]>>>{[[[]())<[]()>]}>}{{{(<[]<>><
+{[{{[(<[[[({[{[]()}[[]]]<<<>[]><()()>>})][[(([<>{}]{{}()}){<{}<>>{[]<>}})[{({}<>)}]]<<{(<><>)<{}()>}<(<>())<<
+<{<{{[<[<{<(([[]{}])[[{}{}]{()[]}])<<{()()}{()<>)>>>}<[<[[{}{}][()[]]]<<[]()>(<>[])>>[(([])
+(([{([<<{{((({()()}[()<>])({<><>}))<<{[][]}[{}()]>{([]{})}>)}}(<<{(<[]()>{[]()})((()()){<><
+[[{<{{{{<(<{{{()[]}{{}[]}}}><<<<{}[]>{{}()}><[{}<>](()[])>>{{({}()><(){}>}<{[]()}[{}]>}>)>[[[{[[{}<>]<()()>][
+[(<<{[{([{[[[{(){}}]<[[][]][<>[]]>]<[<()[]>(()<>)]<<[]()>{[]<>}>>]<<{<{}{}>{{}<>}}{<<><>>[{}<>]}>[
+<[{[({[[[[([([[]<>]<<>{}>)(<{}[]>[<><>])]{[[[]<>}{<><>}]{(()())[()[]]}}){<(<()[]><{}{}>)>{((<><>)[<><>]){{<>
+{([((<{[<({{(<[]>({}{})]{[<>{}]<{}()>}}{([<>{}]<(){}>)[[<>{}](())]}})>[{{<[<<>[]>({}[])]<<{}{}>{
+[<<{([{{{([(<[<>[]][()<>]>(<[]()><<>[]>))(((()()){{}()})<<<>{}>[()<>]>)][{({[]{}}(<><>))[{(){}]]}{<([]<>)
+{[<(([[[{{[{<(<><>)<<>{}>>}]{<{<<><>>}>{[{[]()}[<><>]]([()()][()()])}}}<[{(<()<>>{{}<>})}]{{[<()>{{}[]}]{{{}
+[<[{({{{[<[({<<>{}>{{}{}}})<((<>{}))[{(){}}]>]><((<{[]()}>[([][])]))[[(<()()><{}{}>)[[{}<>]<<>{}}]]{[[<><>
+([{<(([(((<{({()[]}{[]<>})[{[]{}}]}>(<{<()[]>}(([]{})[[]])>)){{{({{}()})(<<>()><[]<>>)}<[{[]{}}]<(()[]>([](
diff --git a/2021/10/testinput b/2021/10/testinput
new file mode 100644
index 0000000..b1518d9
--- /dev/null
+++ b/2021/10/testinput
@@ -0,0 +1,10 @@
+[({(<(())[]>[[{[]{<()<>>
+[(()[<>])]({[<{<<[]>>(
+{([(<{}[<>[]}>{[]{[(<()>
+(((({<>}<{<{<>}{[]{[]{}
+[[<[([]))<([[{}[[()]]]
+[{[{({}]{}}([{[{{{}}([]
+{<[[]]>}<{[{[{[]{()[[[]
+[<(<(<(<{}))><([]([]()
+<{([([[(<>()){}]>(<<{{
+<{([{{}}[<[[[<>{}]]]>[]]
diff --git a/2021/11/code.tl b/2021/11/code.tl
new file mode 100644
index 0000000..9dc724b
--- /dev/null
+++ b/2021/11/code.tl
@@ -0,0 +1,78 @@
+(defstruct board ()
+  w h a s
+
+  (:postinit (bo)
+    (set bo.s (* bo.w bo.h)))
+
+  (:method count-flashes (bo)
+    (sum bo.a (op countql #\0)))
+
+  (:method all-flash (bo)
+    (eql bo.s bo.(count-flashes)))
+
+  (:method lambda (me x y)
+    (if (or (minusp x)
+            (minusp y)
+            (<= me.w x)
+            (<= me.h y))
+      #\0
+      [[me.a y] x]))
+
+  (:method lambda-set (me x y nv)
+    (unless (or (minusp x)
+                (minusp y)
+                (<= me.w x)
+                (<= me.h y))
+      (set [[me.a y] x] nv))))
+
+(defmacro forxy (x y bo . body)
+  ^(each-prod ((,y 0..(qref ,bo h))
+               (,x 0..(qref ,bo w)))
+     ,*body))
+
+(defmacro incnz (place)
+  (with-gensyms (p)
+    ^(placelet ((,p (read-once ,place)))
+       (if (eql #\0 ,p) #\0 (inc ,p)))))
+
+(defmacro mincnz (. places)
+  ^(progn ,*(mapcar (ret ^(incnz ,@1)) places)))
+
+(defun read-board-file (: (name "input"))
+  (flow (file-get-lines name)
+    vec-list
+    (new board
+         h (len @1)
+         w (len (first @1))
+         a @1)))
+
+(defmeth board step (bo)
+  (forxy x y bo
+    (inc [bo x y]))
+  (let ((flashed t))
+    (while flashed
+      (zap flashed)
+      (forxy x y bo
+        (when (> [bo x y] #\9)
+          (set flashed t
+               [bo x y] #\0)
+          (let ((x- (pred x)) (x+ (succ x))
+                (y- (pred y)) (y+ (succ y)))
+            ;; "multi increment, from non-zero"
+            (mincnz [bo x- y-] [bo x  y-] [bo x+ y-]
+                    [bo x- y]             [bo x+ y]
+                    [bo x- y+] [bo x  y+] [bo x+ y+]))))))
+  bo)
+
+(defun solve-part-one (: (name "input"))
+  (let ((bo (read-board-file name))
+        (tf 0))
+    (dotimes (i 100 tf)
+      (inc tf bo.(step).(count-flashes)))))
+
+(defun solve-part-two (: (name "input"))
+  (for ((bo (read-board-file name))
+        (i 0))
+       ((not bo.(all-flash)) i)
+       (bo.(step)
+        (inc i))))
diff --git a/2021/11/input b/2021/11/input
new file mode 100644
index 0000000..497e9f0
--- /dev/null
+++ b/2021/11/input
@@ -0,0 +1,10 @@
+8258741254
+3335286211
+8468661311
+6164578353
+2138414553
+1785385447
+3441133751
+3586862837
+7568272878
+6833643144
diff --git a/2021/11/testinput b/2021/11/testinput
new file mode 100644
index 0000000..03743f6
--- /dev/null
+++ b/2021/11/testinput
@@ -0,0 +1,10 @@
+5483143223
+2745854711
+5264556173
+6141336146
+6357385478
+4167524645
+2176841721
+6882881134
+4846848554
+5283751526
diff --git a/2021/11/testinput-small b/2021/11/testinput-small
new file mode 100644
index 0000000..ae21dd2
--- /dev/null
+++ b/2021/11/testinput-small
@@ -0,0 +1,5 @@
+11111
+19991
+19191
+19991
+11111
diff --git a/2021/12/input b/2021/12/input
new file mode 100644
index 0000000..756681b
--- /dev/null
+++ b/2021/12/input
@@ -0,0 +1,23 @@
+pn-TY
+rp-ka
+az-aw
+al-IV
+pn-co
+end-rp
+aw-TY
+rp-pn
+al-rp
+end-al
+IV-co
+end-TM
+co-TY
+TY-ka
+aw-pn
+aw-IV
+pn-IV
+IV-ka
+TM-rp
+aw-PD
+start-IV
+start-co
+start-pn
diff --git a/2021/12/one.tl b/2021/12/one.tl
new file mode 100644
index 0000000..70e36d5
--- /dev/null
+++ b/2021/12/one.tl
@@ -0,0 +1,49 @@
+(defvar %cave-hash% (hash))
+
+(defstruct cave ()
+  name
+  neighbors
+
+  (:postinit (cv)
+    (assert cv.name)
+    (set [%cave-hash% cv.name] cv)))
+
+(defstruct small-cave cave
+  (:method visit (cv path fn)
+    (unless (member cv path)
+      (push cv path)
+      (each ((n cv.neighbors))
+        n.(visit path fn)))))
+
+(defstruct big-cave cave
+  (:method visit (cv path fn)
+    (push cv path)
+    (each ((n cv.neighbors))
+      n.(visit path fn))))
+
+(defstruct end-cave cave
+  (:method visit (cv path fn)
+    (push cv path)
+    [fn path]))
+
+(defun ensure-cave (name)
+  (or [%cave-hash% name]
+      (set [%cave-hash% name]
+           (match-case name
+             ("end" (new end-cave name name))
+             (@[all @str chr-islower] (new small-cave name name))
+             (@else (new big-cave name name))))))
+
+(defun read-caves (: (name "input"))
+  (with-stream (s (open-file name))
+    (whilet ((line (get-line s)))
+      (match `@a-@b` line
+        (let ((ca (ensure-cave a))
+              (cb (ensure-cave b)))
+          (pushnew cb ca.neighbors)
+          (pushnew ca cb.neighbors))))))
+
+(defun find-paths (fn)
+  (let ((start [%cave-hash% "start"]))
+    (assert start)
+    start.(visit nil fn)))
diff --git a/2021/12/testinput b/2021/12/testinput
new file mode 100644
index 0000000..6fd8c41
--- /dev/null
+++ b/2021/12/testinput
@@ -0,0 +1,7 @@
+start-A
+start-b
+A-c
+A-b
+b-d
+A-end
+b-end
diff --git a/2021/12/two.tl b/2021/12/two.tl
new file mode 100644
index 0000000..69f179a
--- /dev/null
+++ b/2021/12/two.tl
@@ -0,0 +1,68 @@
+(defvar %cave-hash% (hash))
+
+(defstruct cave ()
+  name
+  neighbors
+
+  (:postinit (cv)
+    (assert cv.name)
+    (set [%cave-hash% cv.name] cv)))
+
+(defstruct end-cave cave
+  (:method visit (cv path fn)
+    (push cv path)
+    [fn (remq t path)]))
+
+(defstruct start-cave cave
+  (:method visit (cv path fn)
+    (unless (member cv path)
+      (push cv path)
+      (each ((n cv.neighbors))
+        n.(visit path fn)))))
+
+(defstruct small-cave cave
+  (:method visit (cv path fn)
+    (let ((in-path (member cv path)))
+      (when (or (not in-path)
+                (not (member t path)))
+        (push cv path)
+        (if in-path
+          (push t path))
+        (each ((n cv.neighbors))
+          n.(visit path fn))))))
+
+(defstruct big-cave cave
+  (:method visit (cv path fn)
+    (push cv path)
+    (each ((n cv.neighbors))
+      n.(visit path fn))))
+
+(defun ensure-cave (name)
+  (or [%cave-hash% name]
+      (set [%cave-hash% name]
+           (match-case name
+             ("end" (new end-cave name name))
+             ("start" (new start-cave name name))
+             (@[all @str chr-islower] (new small-cave name name))
+             (@else (new big-cave name name))))))
+
+(defun read-caves (: (name "input"))
+  (with-stream (s (open-file name))
+    (whilet ((line (get-line s)))
+      (match `@a-@b` line
+        (let ((ca (ensure-cave a))
+              (cb (ensure-cave b)))
+          (pushnew cb ca.neighbors)
+          (pushnew ca cb.neighbors))))))
+
+(defun find-paths (fn)
+  (let ((start [%cave-hash% "start"]))
+    (assert start)
+    start.(visit nil fn)))
+
+(defun solve (: (name "input"))
+  (let (paths)
+    (read-caves name)
+    (find-paths (opip reverse (mapcar .name) (push @1 paths)))
+    (mapdo [chain (ap join-with ",") pprinl] paths)
+    (len paths)))
diff --git a/2021/17/code.tl b/2021/17/code.tl
new file mode 100644
index 0000000..af76de0
--- /dev/null
+++ b/2021/17/code.tl
@@ -0,0 +1,46 @@
+(defstruct spec ()
+  x0 x1
+  y0 y1)
+
+(defun read-input (: (name "input"))
+  (flow name
+    file-get-string
+    (match `target area: x=@x0..@x1, y=@y0..@y1\n@nil` @1
+      (new spec x0 (toint x0) x1 (toint x1) y0 (toint y0) y1 (toint y1)))))
+
+(defun simulate-shot (sp xv yv)
+  (let ((x0 sp.x0) (x1 sp.x1)
+        (y0 sp.y0) (y1 sp.y1))
+  (for ((x 0) (y 0) (maxy -1000)) () ()
+    (cond
+      ((or (< y y0) (> x x1))
+       (return))
+      ((and (<= x0 x x1) (<= y0 y y1))
+       (return maxy)))
+    (inc x xv)
+    (inc y yv)
+    (upd maxy (max y maxy))
+    (dec xv (signum xv))
+    (dec yv 1))))
+
+(defun solve-one (: (name :))
+  (let ((sp (read-input name)))
+    (flow
+      (build
+        (each-prod ((xv 1..40)
+                    (yv 1..700))
+          (iflet ((maxy (simulate-shot sp xv yv)))
+            (add (list xv yv maxy)))))
+      (find-max @1 : caddr))))
+
+(defun solve-two (: (name :))
+  (let ((sp (read-input name)))
+    (flow
+      (build
+        (each-prod ((xv 1..300)
+                    (yv -100..400))
+          (iflet ((maxy (simulate-shot sp xv yv)))
+            (add (list xv yv maxy)))))
+      (mapcar (ap list @1 @2))
+      uniq
+      len)))
diff --git a/2021/17/errors.err b/2021/17/errors.err
new file mode 100644
index 0000000..6bff0b0
--- /dev/null
+++ b/2021/17/errors.err
@@ -0,0 +1,2 @@
+defmicro: error: expansion is larger than original form: switch to defmacro.
+[6n[999C[6n[98D1> 
diff --git a/2021/17/input b/2021/17/input
new file mode 100644
index 0000000..d9179a5
--- /dev/null
+++ b/2021/17/input
@@ -0,0 +1 @@
+target area: x=240..292, y=-90..-57
diff --git a/2021/17/testinput b/2021/17/testinput
new file mode 100644
index 0000000..a07e02d
--- /dev/null
+++ b/2021/17/testinput
@@ -0,0 +1 @@
+target area: x=20..30, y=-10..-5
diff --git a/2021/18/code.tl b/2021/18/code.tl
new file mode 100644
index 0000000..92b17e3
--- /dev/null
+++ b/2021/18/code.tl
@@ -0,0 +1,75 @@
+(defun read-string (str)
+  (flow str (mapcar (relate '(#\[ #\] #\,) '(#\( #\) #\space))) read))
+
+(defun read-input (: (name "input"))
+  (flow name file-get-lines (mapcar read-string)))
+
+(defun ladd (n sn)
+  (tree-case sn
+    ((a b) ^(,(ladd n a) ,b))
+    (m (+ n m))))
+
+(defun radd (sn n)
+  (tree-case sn
+    ((a b) ^(,a ,(radd b n)))
+    (m (+ m n))))
+
+(defun explode (sn)
+  (match-case sn
+    (^(((((,a ,b) ,x) ,y) ,z) ,w) ^((((0 ,(ladd b x)) ,y) ,z) ,w))
+    (^((((,x (,a ,b)) ,y) ,z) ,w) ^((((,(radd x a) 0) ,(ladd b y)) ,z) ,w))
+    (^(((,y ((,a ,b) ,x)) ,z) ,w) ^(((,(radd y a) (0 ,(ladd b x))) ,z) ,w))
+    (^(((,y (,x (,a ,b))) ,z) ,w) ^(((,y (,(radd x a) 0)) ,(ladd b z)) ,w))
+    (^((,z (((,a ,b) ,x) ,y)) ,w) ^((,(radd z a) ((0 ,(ladd b x)) ,y)) ,w))
+    (^((,z ((,x (,a ,b)) ,y)) ,w) ^((,z ((,(radd x a) 0) ,(ladd b y))) ,w))
+    (^((,z (,y ((,a ,b) ,x))) ,w) ^((,z (,(radd y a) (0 ,(ladd b x)))) ,w))
+    (^((,z (,y (,x (,a ,b)))) ,w) ^((,z (,y (,(radd x a) 0))) ,(ladd b w)))
+    (^(,w ((((,a ,b) ,x) ,y) ,z)) ^(,(radd w a) (((0 ,(ladd b x)) ,y) ,z)))
+    (^(,w (((,x (,a ,b)) ,y) ,z)) ^(,w (((,(radd x a) 0) ,(ladd b y)) ,z)))
+    (^(,w ((,y ((,a ,b) ,x)) ,z)) ^(,w ((,(radd y a) (0 ,(ladd b x))) ,z)))
+    (^(,w ((,y (,x (,a ,b))) ,z)) ^(,w ((,y (,(radd x a) 0)) ,(ladd b z))))
+    (^(,w (,z (((,a ,b) ,x) ,y))) ^(,w (,(radd z a) ((0 ,(ladd b x)) ,y))))
+    (^(,w (,z ((,x (,a ,b)) ,y))) ^(,w (,z ((,(radd x a) 0) ,(ladd b y)))))
+    (^(,w (,z (,y ((,a ,b) ,x)))) ^(,w (,z (,(radd y a) (0 ,(ladd b x))))))
+    (^(,w (,z (,y (,x (,a ,b))))) ^(,w (,z (,y (,(radd x a) 0)))))
+    (@else else)))
+
+(defun splt (sn)
+  (tree-case sn
+    ((a b)
+     (let ((as (splt a))
+           (bs (splt b)))
+       (cond
+         ((neq a as) ^(,as ,b))
+         ((neq b bs) ^(,a ,bs))
+         (t sn))))
+    (m (if (< m 10)
+         m
+         (let* ((x (trunc m 2))
+                (y (- m x)))
+           ^(,x ,y))))))
+
+(defun reduce (sn)
+  (let (sn*)
+    (while* (neq sn* sn)
+      (while* (neq sn* sn)
+        (shift sn* sn (explode sn)))
+      (shift sn* sn (splt sn)))
+    sn))
+
+(defun add (sn0 sn1)
+  (reduce (list sn0 sn1)))
+
+(defun mag (sn)
+  (tree-case sn
+    ((a b) (+ (* 3 (mag a)) (* 2 (mag b))))
+    (m m)))
+
+(defun solve-one (: (name :))
+  (flow name read-input (reduce-left add) mag))
+
+(defun solve-two (: (name :))
+  (flow name read-input (comb @1 2)
+    (mappend [juxt [chain [apf add] mag]
+                   [chain [apf [flipargs add]] mag]])
+    find-max))
diff --git a/2021/18/code2.tl b/2021/18/code2.tl
new file mode 100644
index 0000000..58e2e32
--- /dev/null
+++ b/2021/18/code2.tl
@@ -0,0 +1,75 @@
+(defun read-string (str)
+  (flow str (mapcar (relate '(#\[ #\] #\,) '(#\( #\) #\space))) read))
+
+(defun read-input (: (name "input"))
+  (flow name file-get-lines (mapcar read-string)))
+
+(defun ladd (n sn)
+  (tree-case sn
+    ((a b) ^(,(ladd n a) ,b))
+    (m (+ n m))))
+
+(defun radd (sn n)
+  (tree-case sn
+    ((a b) ^(,a ,(radd b n)))
+    (m (+ m n))))
+
+(defun explode (sn)
+  (tree-case sn
+    ((((((a b) x) y) z) w) ^((((0 ,(ladd b x)) ,y) ,z) ,w))
+    (((((x (a b)) y) z) w) ^((((,(radd x a) 0) ,(ladd b y)) ,z) ,w))
+    ((((y ((a b) x)) z) w) ^(((,(radd y a) (0 ,(ladd b x))) ,z) ,w))
+    ((((y (x (a b))) z) w) ^(((,y (,(radd x a) 0)) ,(ladd b z)) ,w))
+    (((z (((a b) x) y)) w) ^((,(radd z a) ((0 ,(ladd b x)) ,y)) ,w))
+    (((z ((x (a b)) y)) w) ^((,z ((,(radd x a) 0) ,(ladd b y))) ,w))
+    (((z (y ((a b) x))) w) ^((,z (,(radd y a) (0 ,(ladd b x)))) ,w))
+    (((z (y (x (a b)))) w) ^((,z (,y (,(radd x a) 0))) ,(ladd b w)))
+    ((w ((((a b) x) y) z)) ^(,(radd w a) (((0 ,(ladd b x)) ,y) ,z)))
+    ((w (((x (a b)) y) z)) ^(,w (((,(radd x a) 0) ,(ladd b y)) ,z)))
+    ((w ((y ((a b) x)) z)) ^(,w ((,(radd y a) (0 ,(ladd b x))) ,z)))
+    ((w ((y (x (a b))) z)) ^(,w ((,y (,(radd x a) 0)) ,(ladd b z))))
+    ((w (z (((a b) x) y))) ^(,w (,(radd z a) ((0 ,(ladd b x)) ,y))))
+    ((w (z ((x (a b)) y))) ^(,w (,z ((,(radd x a) 0) ,(ladd b y)))))
+    ((w (z (y ((a b) x)))) ^(,w (,z (,(radd y a) (0 ,(ladd b x))))))
+    ((w (z (y (x (a b))))) ^(,w (,z (,y (,(radd x a) 0)))))
+    (else else)))
+
+(defun splt (sn)
+  (tree-case sn
+    ((a b)
+     (let ((as (splt a))
+           (bs (splt b)))
+       (cond
+         ((neq a as) ^(,as ,b))
+         ((neq b bs) ^(,a ,bs))
+         (t sn))))
+    (m (if (< m 10)
+         m
+         (let* ((x (trunc m 2))
+                (y (- m x)))
+           ^(,x ,y))))))
+
+(defun reduce (sn)
+  (let (sn*)
+    (while* (neq sn* sn)
+      (while* (neq sn* sn)
+        (shift sn* sn (explode sn)))
+      (shift sn* sn (splt sn)))
+    sn))
+
+(defun add (sn0 sn1)
+  (reduce (list sn0 sn1)))
+
+(defun mag (sn)
+  (tree-case sn
+    ((a b) (+ (* 3 (mag a)) (* 2 (mag b))))
+    (m m)))
+
+(defun solve-one (: (name :))
+  (flow name read-input (reduce-left add) mag))
+
+(defun solve-two (: (name :))
+  (flow name read-input (comb @1 2)
+    (mappend [juxt [chain [apf add] mag]
+                   [chain [apf [flipargs add]] mag]])
+    find-max))
diff --git a/2021/18/input b/2021/18/input
new file mode 100644
index 0000000..5116955
--- /dev/null
+++ b/2021/18/input
@@ -0,0 +1,100 @@
+[[2,[2,[4,0]]],[6,1]]
+[[3,[4,[2,4]]],[[6,9],[6,1]]]
+[7,[8,[8,[0,8]]]]
+[[[[2,9],5],5],[[[0,1],8],[[7,9],5]]]
+[[[[3,0],[7,0]],[[9,6],[1,9]]],4]
+[[[0,[4,8]],8],[[[2,1],9],6]]
+[[[5,[7,7]],[[9,6],2]],[[[5,8],8],0]]
+[[0,3],[[8,2],[6,[2,2]]]]
+[[[9,0],[4,[4,7]]],[7,[[9,1],9]]]
+[0,[7,[1,1]]]
+[[[4,[0,1]],[[1,0],8]],[[[3,9],[0,1]],[[9,1],[8,8]]]]
+[[[6,0],3],2]
+[[[[4,1],[2,7]],[9,[8,9]]],[[3,0],0]]
+[[[[2,4],[8,7]],[9,[9,7]]],[[[2,5],6],9]]
+[[7,6],[[4,[2,4]],[3,8]]]
+[[7,2],[[8,8],7]]
+[[[[6,0],4],[[4,7],4]],[[6,[2,7]],[[6,5],3]]]
+[[[[8,8],[7,6]],4],5]
+[[0,[[6,9],[7,9]]],[9,5]]
+[9,[[[0,4],6],[[7,0],0]]]
+[[[[4,4],0],[3,[3,9]]],[[7,5],[5,[7,2]]]]
+[[[8,3],[[8,5],[4,4]]],[0,[0,3]]]
+[[9,[3,[6,7]]],[[7,0],[[9,2],7]]]
+[[[3,7],[[3,6],9]],7]
+[[2,[2,[5,7]]],[[[6,4],5],[4,7]]]
+[[[[9,0],2],[[4,4],6]],[[[3,2],[5,5]],[[5,9],7]]]
+[[[[2,5],4],[8,5]],6]
+[[[3,2],[[1,7],5]],[[8,1],[1,[1,2]]]]
+[8,[[3,[5,4]],5]]
+[[[2,[5,9]],[1,3]],[[[2,3],[8,3]],[[5,1],[8,9]]]]
+[[[2,0],[[3,3],[4,7]]],[[[8,7],[7,4]],1]]
+[[[[7,4],9],[3,[4,1]]],[[[8,4],5],7]]
+[[[[0,2],9],3],[9,[5,3]]]
+[3,4]
+[[[1,[0,2]],[[9,9],[8,2]]],6]
+[[[[2,9],[3,5]],9],[[9,3],[3,[6,7]]]]
+[[0,[[4,6],4]],[2,[5,2]]]
+[9,[[9,[6,8]],8]]
+[3,[[[1,2],[0,9]],[[4,9],1]]]
+[[[[8,7],[1,7]],[[2,6],[8,5]]],[3,[[8,0],[6,9]]]]
+[[8,[[4,9],7]],[3,[9,4]]]
+[[0,[[3,2],[2,2]]],0]
+[[[2,7],[[5,7],4]],[[[6,0],[2,1]],[[4,1],[1,6]]]]
+[[[[9,6],[0,3]],[[0,6],[0,4]]],[[[3,7],[6,7]],7]]
+[[[[1,1],6],[[5,6],4]],[[5,[0,7]],1]]
+[[[3,9],[[7,3],[1,5]]],[[[1,2],3],[0,[5,6]]]]
+[[[[4,4],[0,5]],6],[[7,[2,0]],6]]
+[[[[2,2],6],9],[[[9,1],2],[[8,6],8]]]
+[[[[5,0],8],[[5,7],7]],[6,[5,3]]]
+[[[[8,2],[8,4]],1],[[1,[7,3]],8]]
+[[[[3,2],2],[[4,9],[5,4]]],[[[9,2],4],[5,[6,0]]]]
+[[1,[[0,6],0]],[[[1,5],2],[[6,0],[3,7]]]]
+[4,[7,[6,[3,3]]]]
+[[[0,[2,5]],2],5]
+[[[0,[5,7]],9],[[[2,3],[3,4]],[[0,4],9]]]
+[[3,1],[[[4,1],9],[[0,5],[8,6]]]]
+[[9,[2,0]],[[0,[1,7]],[9,[6,4]]]]
+[[[[6,5],5],5],[5,8]]
+[[[[2,8],[1,3]],[[5,4],2]],[[[0,8],[5,1]],[9,[5,6]]]]
+[[[[6,9],7],[9,7]],2]
+[[[[1,7],8],[8,7]],[[[3,5],4],8]]
+[[[[1,8],[1,0]],0],[[7,1],5]]
+[[[9,[6,8]],3],[[5,1],[4,[8,2]]]]
+[[[0,[2,1]],1],[3,[9,[5,5]]]]
+[[2,5],[2,5]]
+[[[[1,1],[8,3]],[[1,9],[4,9]]],[[5,[4,8]],[[5,0],0]]]
+[[[0,7],[[3,4],1]],[[[1,2],[2,9]],[[2,0],9]]]
+[3,2]
+[[[9,[8,2]],[7,3]],7]
+[[[[6,9],9],[3,2]],0]
+[[3,[[6,1],8]],6]
+[[[[5,9],9],[[4,4],7]],[7,5]]
+[1,[[2,8],0]]
+[[2,[0,6]],[[[3,3],[0,4]],8]]
+[[[[4,8],9],[0,[3,0]]],[[0,[3,1]],[8,[7,4]]]]
+[[[6,[8,0]],[0,[8,9]]],[3,8]]
+[[[[0,8],[9,4]],[1,[2,0]]],1]
+[[7,6],[[[0,2],9],3]]
+[[[[1,0],3],2],1]
+[[[[1,2],8],5],7]
+[0,[[3,0],7]]
+[[7,[[0,9],[8,4]]],[[2,0],[[2,8],1]]]
+[[[1,8],[[8,1],1]],[3,[8,9]]]
+[4,[[3,7],[[5,2],9]]]
+[[[[3,8],[2,9]],[3,9]],[[[3,7],[6,9]],[[1,7],2]]]
+[9,[[[3,7],9],[[4,9],[8,6]]]]
+[[7,[3,9]],[0,7]]
+[[[1,6],0],[[7,[8,1]],[6,3]]]
+[[[[3,9],3],[[2,6],[8,0]]],[[3,3],9]]
+[[[1,2],[1,6]],[[1,[4,2]],0]]
+[[[0,[3,0]],2],[[7,[9,4]],[6,8]]]
+[6,[[[3,1],1],5]]
+[[[3,4],[[5,9],[1,1]]],[[2,[0,1]],3]]
+[[2,[[1,5],7]],[0,2]]
+[[1,[[6,7],7]],4]
+[6,[5,[[3,2],[6,8]]]]
+[[[3,9],[[4,0],6]],[8,[3,[5,2]]]]
+[[5,[[7,3],[2,2]]],[[7,7],7]]
+[[[1,2],[[2,4],[6,1]]],[[0,[4,2]],[[5,7],[2,3]]]]
+[[[8,7],8],[[7,[3,6]],[[1,0],4]]]
diff --git a/2021/18/testinput b/2021/18/testinput
new file mode 100644
index 0000000..70e9071
--- /dev/null
+++ b/2021/18/testinput
@@ -0,0 +1,10 @@
+[[[0,[4,5]],[0,0]],[[[4,5],[2,6]],[9,5]]]
+[7,[[[3,7],[4,3]],[[6,3],[8,8]]]]
+[[2,[[0,8],[3,4]]],[[[6,7],1],[7,[1,6]]]]
+[[[[2,4],7],[6,[0,5]]],[[[6,8],[2,8]],[[2,1],[4,5]]]]
+[7,[5,[[3,8],[1,4]]]]
+[[2,[2,2]],[8,[8,1]]]
+[2,9]
+[1,[[[9,3],9],[[9,0],[0,7]]]]
+[[[5,[7,4]],7],1]
+[[[[4,2],2],6],[8,7]]
diff --git a/2021/18/testinput2 b/2021/18/testinput2
new file mode 100644
index 0000000..1368dc4
--- /dev/null
+++ b/2021/18/testinput2
@@ -0,0 +1,10 @@
+[[[0,[5,8]],[[1,7],[9,6]]],[[4,[1,2]],[[1,4],2]]]
+[[[5,[2,8]],4],[5,[[9,9],0]]]
+[6,[[[6,2],[5,6]],[[7,6],[4,7]]]]
+[[[6,[0,7]],[0,9]],[4,[9,[9,0]]]]
+[[[7,[6,4]],[3,[1,3]]],[[[5,5],1],9]]
+[[6,[[7,3],[3,2]]],[[[3,8],[5,7]],4]]
+[[[[5,4],[7,7]],8],[[8,3],8]]
+[[9,3],[[9,9],[6,[4,9]]]]
+[[2,[[7,7],7]],[[5,8],[[9,3],[0,2]]]]
+[[[[5,2],5],[8,[3,7]]],[[5,[7,5]],[4,4]]]
diff --git a/2021/19/code.tl b/2021/19/code.tl
new file mode 100644
index 0000000..97dd3f3
--- /dev/null
+++ b/2021/19/code.tl
@@ -0,0 +1,164 @@
+(defstruct scanner ()
+  id
+  data
+  rot
+  pref
+  delta
+  nei)
+
+(defun read-input (: (name "input"))
+  (with-stream (s (open-file name))
+    (build
+      (let (scnr)
+        (while-match-case (get-line s)
+          ("")
+          (`@x,@y,@z` (push (vec (toint x) (toint y) (toint z)) scnr.data))
+          (`--- scanner @n ---` (set scnr (new scanner id (toint n))) (add scnr)))))))
+
+(defmacro x (p) ^[,p 0])
+(defmacro y (p) ^[,p 1])
+(defmacro z (p) ^[,p 2])
+
+(defmacro rot-z (p)
+  (with-gensyms (tp)
+    ^(let ((,tp ,p))
+       (vec (- (y ,tp)) (x ,tp) (z ,tp)))))
+
+(defmacro rot-y (p)
+  (with-gensyms (tp)
+    ^(let ((,tp ,p))
+       (vec (z ,tp) (y ,tp) (- (x ,tp))))))
+
+(defmacro rot-x (p)
+  (with-gensyms (tp)
+    ^(let ((,tp ,p))
+       (vec (x ,tp) (- (z ,tp)) (y ,tp)))))
+
+(defmacro psub (p0 p1)
+  (with-gensyms (tp0 tp1)
+    ^(let ((,tp0 ,p0) (,tp1 ,p1))
+       (vec (- (x ,tp0) (x ,tp1))
+            (- (y ,tp0) (y ,tp1))
+            (- (z ,tp0) (z ,tp1))))))
+
+(defmacro padd (p0 p1)
+  (with-gensyms (tp0 tp1)
+    ^(let ((,tp0 ,p0) (,tp1 ,p1))
+       (vec (+ (x ,tp0) (x ,tp1))
+            (+ (y ,tp0) (y ,tp1))
+            (+ (z ,tp0) (z ,tp1))))))
+
+(defmeth scanner gen-rot (sc)
+  (set sc.rot (vec))
+  (dotimes (i 24)
+    (vec-push sc.rot (vec)))
+
+  (each ((rA sc.data))
+    (let* (                        (rB (rot-x rA)) (rC (rot-x rB)) (rD (rot-x rC))
+           (rE (rot-z rA))         (rF (rot-y rE)) (rG (rot-y rF)) (rH (rot-y rG))
+           (rI (rot-z rE))         (rJ (rot-x rI)) (rK (rot-x rJ)) (rL (rot-x rK))
+           (rM (rot-z rI))         (rN (rot-y rM)) (rO (rot-y rN)) (rP (rot-y rO))
+           (rQ (rot-y rA))         (rR (rot-z rQ)) (rS (rot-z rR)) (rT (rot-z rS))
+           (rU (rot-y (rot-y rQ))) (rV (rot-z rU)) (rW (rot-z rV)) (rX (rot-z rW)))
+      (vec-push [sc.rot  0] rA) (vec-push [sc.rot  1] rB)
+      (vec-push [sc.rot  2] rC) (vec-push [sc.rot  3] rD)
+      (vec-push [sc.rot  4] rE) (vec-push [sc.rot  5] rF)
+      (vec-push [sc.rot  6] rG) (vec-push [sc.rot  7] rH)
+      (vec-push [sc.rot  8] rI) (vec-push [sc.rot  9] rJ)
+      (vec-push [sc.rot 10] rK) (vec-push [sc.rot 11] rL)
+      (vec-push [sc.rot 12] rM) (vec-push [sc.rot 13] rN)
+      (vec-push [sc.rot 14] rO) (vec-push [sc.rot 15] rP)
+      (vec-push [sc.rot 16] rQ) (vec-push [sc.rot 17] rR)
+      (vec-push [sc.rot 18] rS) (vec-push [sc.rot 19] rT)
+      (vec-push [sc.rot 20] rU) (vec-push [sc.rot 21] rV)
+      (vec-push [sc.rot 22] rW) (vec-push [sc.rot 23] rX))))
+
+(defun overlap-delta (pvec0 pvec1 amt)
+  (each-prod ((p0 pvec0)
+              (p1 pvec1))
+    (let* ((delta (psub p1 p0))
+           (novl (len (isec pvec0
+                            (mapcar (do psub @1 delta) pvec1)))))
+      (when (>= novl amt)
+        (return delta)))))
+
+(defun overlaps-with (s0 s1 : (amt 12))
+  (for* ((r 0) (r0 [s0.rot (or s0.pref 0)]) (rot1 s1.rot) (n (len rot1)))
+        ((< r n))
+        ((inc r))
+    (whenlet ((delta (overlap-delta r0 [rot1 r] amt)))
+      (return (cons delta r)))))
+
+(defun link-graph (slist)
+  (let ((sf (car slist))
+        (backref)
+        (count 0))
+    (flet ((lnk (s0 s1)
+                (tree-case (overlaps-with s0 s1)
+                  ((delta . r)
+                   (prinl ^(:lap ,s0.id ,s1.id ,r ,delta))
+                   (cond
+                     ((and (neq s0 sf) (null s0.pref))
+                      (push (cons s0 s1) backref))
+                     (t
+                       (set s1.pref r)
+                       (push (list* s1 r delta) s0.nei)))))))
+      (each-match ((@s0 @s1) (comb slist 2))
+        (prinl ^(,(inc count) ,s0.id ,s1.id))
+        (cond
+          ((null s1.pref) (lnk s0 s1))
+          ((null s0.pref) (lnk s1 s0))))
+      (while backref
+        (set count 0)
+        (put-line "backref")
+        (each-match ((@s0 . @s1) (zap backref))
+          (prinl ^(,(inc count) ,s0.id ,s1.id))
+          (cond
+            ((null s1.pref) (lnk s0 s1))
+            ((null s0.pref) (lnk s1 s0))))))
+    (keep-if .nei slist)))
+
+(defun assemble-map (slist)
+  (let ((out (vec)))
+    (labels ((visit (sn r delta)
+               (prinl ^(:visit ,sn.id ,r))
+               (set sn.delta delta)
+               (each ((p [sn.rot r]))
+                 (vec-push out (psub p delta)))
+               (each-match ((@n @nr . @ndelta) sn.nei)
+                 (visit n nr (padd delta ndelta)))))
+      (visit (car slist) 0 #(0 0 0)))
+      (prinl ^(:len out ,(len out)))
+      (uniq out)))
+
+;; answer is 438
+(defun solve-one (: (name :))
+  (flow name
+    read-input
+    (progn (mapdo .(gen-rot) @1) @1)
+    link-graph
+    assemble-map))
+
+(defun manhattan (p)
+  [sum p abs])
+
+(defun max-manhattan-delta (slist)
+  (let ((maxhattan 0))
+    (each-match ((@s0 @s1) (comb slist 2))
+      (prinl  ^(:delta ,s0.id ,s0.delta ,s1.id ,s1.delta))
+      (let ((mhdelta (manhattan (psub s0.delta s1.delta))))
+        (upd maxhattan (max mhdelta))))
+    maxhattan))
+
+;; answer is 11985
+(defun solve-two (: (name :))
+  (flow name
+    read-input
+    (let ((orig @1))
+      (flow orig
+        (progn (mapdo .(gen-rot) @1) @1)
+        link-graph
+        assemble-map)
+      (flow orig
+        (keep-if .delta)
+        max-manhattan-delta))))
diff --git a/2021/19/input b/2021/19/input
new file mode 100644
index 0000000..f98aaec
--- /dev/null
+++ b/2021/19/input
@@ -0,0 +1,975 @@
+--- scanner 0 ---
+592,476,409
+451,462,-479
+840,-352,632
+619,398,366
+584,458,-482
+794,-340,778
+462,524,-410
+-26,36,-166
+-518,712,-554
+-524,544,-667
+-364,758,518
+542,430,440
+87,115,17
+-380,-427,-609
+863,-333,586
+-422,566,-511
+-756,-510,685
+-806,-704,722
+-408,800,678
+-450,839,466
+-514,-291,-633
+-485,-380,-513
+557,-392,-606
+-788,-610,775
+481,-347,-441
+578,-334,-581
+
+--- scanner 1 ---
+-583,-765,-719
+632,295,485
+636,327,350
+-657,380,343
+599,-732,-645
+-621,253,313
+678,357,398
+-736,626,-578
+-503,-949,296
+-740,733,-663
+-719,286,402
+554,772,-816
+590,-602,633
+692,727,-916
+-601,-833,-688
+538,-677,-732
+-622,-850,299
+-13,-191,-155
+580,-630,724
+-562,-977,-745
+566,-781,-633
+538,732,-855
+-499,-953,313
+-72,-48,-13
+686,-608,696
+-800,649,-736
+
+--- scanner 2 ---
+-516,-454,605
+408,-415,759
+-693,-252,-394
+809,-355,-358
+594,799,-361
+539,788,-397
+-538,-352,761
+-430,654,790
+362,648,691
+420,627,666
+-496,532,862
+-34,99,76
+767,-316,-493
+-684,-448,718
+-752,-304,-381
+615,807,-538
+-649,805,-656
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+
+--- scanner 3 ---
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+
+--- scanner 4 ---
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+
+--- scanner 5 ---
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+
+--- scanner 6 ---
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+
+--- scanner 7 ---
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+--- scanner 8 ---
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+--- scanner 9 ---
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+--- scanner 10 ---
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+
+--- scanner 11 ---
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+
+--- scanner 12 ---
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+
+--- scanner 13 ---
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+--- scanner 14 ---
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+
+--- scanner 15 ---
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+
+--- scanner 16 ---
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+
+--- scanner 17 ---
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+
+--- scanner 18 ---
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+
+--- scanner 19 ---
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+
+--- scanner 20 ---
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+
+--- scanner 21 ---
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+
+--- scanner 22 ---
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+
+--- scanner 23 ---
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+
+--- scanner 24 ---
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+
+--- scanner 25 ---
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+
+--- scanner 26 ---
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+
+--- scanner 27 ---
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+
+--- scanner 28 ---
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+
+--- scanner 29 ---
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+
+--- scanner 30 ---
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+
+--- scanner 31 ---
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+
+--- scanner 32 ---
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+
+--- scanner 33 ---
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+
+--- scanner 34 ---
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diff --git a/2021/19/input.txr b/2021/19/input.txr
new file mode 100644
index 0000000..adbc19f
--- /dev/null
+++ b/2021/19/input.txr
@@ -0,0 +1,9 @@
+@(collect)
+--- scanner @s ---
+@  (collect :vars (p))
+@x,@y,@z
+@  (bind p @(vec (toint x) (toint y) (toint z)))
+@  (until)
+
+@  (end)
+@(end)
diff --git a/2021/19/scratch b/2021/19/scratch
new file mode 100644
index 0000000..af3a476
--- /dev/null
+++ b/2021/19/scratch
@@ -0,0 +1,4 @@
+for each point p0 in vec0
+   for point in p1 in vec1
+     translate vec1 by (p1 - p0)
+     intersect and count
diff --git a/2021/19/testinput b/2021/19/testinput
new file mode 100644
index 0000000..4e496e9
--- /dev/null
+++ b/2021/19/testinput
@@ -0,0 +1,136 @@
+--- scanner 0 ---
+404,-588,-901
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+-789,900,-551
+459,-707,401
+
+--- scanner 1 ---
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+
+--- scanner 2 ---
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+-588,-843,648
+-30,6,44
+-674,560,763
+500,723,-460
+609,671,-379
+-555,-800,653
+-675,-892,-343
+697,-426,-610
+578,704,681
+493,664,-388
+-671,-858,530
+-667,343,800
+571,-461,-707
+-138,-166,112
+-889,563,-600
+646,-828,498
+640,759,510
+-630,509,768
+-681,-892,-333
+673,-379,-804
+-742,-814,-386
+577,-820,562
+
+--- scanner 3 ---
+-589,542,597
+605,-692,669
+-500,565,-823
+-660,373,557
+-458,-679,-417
+-488,449,543
+-626,468,-788
+338,-750,-386
+528,-832,-391
+562,-778,733
+-938,-730,414
+543,643,-506
+-524,371,-870
+407,773,750
+-104,29,83
+378,-903,-323
+-778,-728,485
+426,699,580
+-438,-605,-362
+-469,-447,-387
+509,732,623
+647,635,-688
+-868,-804,481
+614,-800,639
+595,780,-596
+
+--- scanner 4 ---
+727,592,562
+-293,-554,779
+441,611,-461
+-714,465,-776
+-743,427,-804
+-660,-479,-426
+832,-632,460
+927,-485,-438
+408,393,-506
+466,436,-512
+110,16,151
+-258,-428,682
+-393,719,612
+-211,-452,876
+808,-476,-593
+-575,615,604
+-485,667,467
+-680,325,-822
+-627,-443,-432
+872,-547,-609
+833,512,582
+807,604,487
+839,-516,451
+891,-625,532
+-652,-548,-490
+30,-46,-14
diff --git a/2021/20/code.tl b/2021/20/code.tl
new file mode 100644
index 0000000..dcc4933
--- /dev/null
+++ b/2021/20/code.tl
@@ -0,0 +1,73 @@
+(defvarl h2b (relate ".#" #(0 1)))
+
+(defvarl b2h ".#")
+
+(defstruct ctx ()
+  alg
+  (hash (hash))
+  grid
+  (min-x 0) (min-y 0)
+  (max-x 0) (max-y 0)
+  toggle
+
+  (:postinit (me)
+    (if (nzerop [me.alg 0])
+      (set me.toggle 0))
+    (each ((line me.grid)
+           (y 0))
+      (each ((bit line)
+             (x 0))
+        (set [me.hash x..y] [h2b bit])
+        (upd me.max-x (max x))
+        (upd me.max-y (max y)))))
+
+  (:method lambda (me x y)
+    (or [me.hash x..y]
+        me.toggle
+        0))
+
+  (:method lambda-set (me x y nv)
+    (set [me.hash x..y] nv)
+    (upd me.max-x (max x))
+    (upd me.min-x (min x))
+    (upd me.max-y (max y))
+    (upd me.min-y (min y)))
+
+  (:method print (me stream pretty-p)
+    (each ((y me.min-y..(succ me.max-y)))
+      (each ((x me.min-x..(succ me.max-x)))
+        (put-char [b2h [me x y]] stream))
+      (put-line : stream))))
+
+(defmeth ctx step (me)
+  (let ((nme (copy me)))
+    (set nme.hash (hash))
+    (each-prod ((y (pred me.min-y)..(ssucc me.max-y))
+                (x (pred me.min-x)..(ssucc me.max-x)))
+      (let* ((x- (pred x)) (x+ (succ x))
+             (y- (pred y)) (y+ (succ y))
+             (bits (flow (vec [me x- y-] [me x y-] [me x+ y-]
+                              [me x- y]  [me x y]  [me x+ y]
+                              [me x- y+] [me x y+] [me x+ y+])
+                     (poly 2))))
+        (set [nme x y] [me.alg bits])))
+    (replace-struct me nme)
+    (upd me.toggle [iff true (op - 1)])
+    me))
+
+(defun read-input (: (name "input"))
+  (flow (file-get-lines name)
+    (match (@alg "" . @grid) @1
+      (new ctx
+           alg [mapcar h2b alg]
+           grid grid))))
+
+;; answers; 5291, 16665.
+(defun solve (steps : (name :))
+  (flow name
+    (read-input)
+    (dotimes (i steps @1)
+      (put-line `step @i`)
+      @1.(step))
+    .hash
+    (count-if plusp @1 cdr)))
diff --git a/2021/20/input b/2021/20/input
new file mode 100644
index 0000000..5ae298c
--- /dev/null
+++ b/2021/20/input
@@ -0,0 +1,102 @@
+#.#.###........##....#.......#..##.#.##...#..##...#..##.......##..##.#..####.#.#..#..#...#.##...##.####..###.#.###.#####...##.#.###..#..#.##...##..####...#..#.#.###....####.####.##.####.#..##.##...#####.##.#.##.#..##.##.##.###.#..##.#.##...###.###..###....#.########..##..#...#....###.####.#######..#.##.##...####.#.#.###.#..#.......#..##..##.##....####.##.#.#.##.#.#.#.##.#..##..##.#..####.#....##.#...#.##.#....#......#...##.##.#.#...#.#.#.#..#.##.#..##...##.#.#.##..###.##.#.###..#####.#...###..#.....#....#..
+
+..#.#...##.......#.####...##....##.###.####.##..###..#####......##.###.##.##.#...#....#####.#####.##
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diff --git a/2021/20/testinput b/2021/20/testinput
new file mode 100644
index 0000000..8fa4bd4
--- /dev/null
+++ b/2021/20/testinput
@@ -0,0 +1,7 @@
+..#.#..#####.#.#.#.###.##.....###.##.#..###.####..#####..#....#..#..##..###..######.###...####..#..#####..##..#.#####...##.#.#..#.##..#.#......#.###.######.###.####...#.##.##..#..#..#####.....#.#....###..#.##......#.....#..#..#..##..#...##.######.####.####.#.#...#.......#..#.#.#...####.##.#......#..#...##.#.##..#...##.#.##..###.#......#.#.......#.#.#.####.###.##...#.....####.#..#..#.##.#....##..#.####....##...##..#...#......#.#.......#.......##..####..#...#.#.#...##..#.#..###..#####........#..####......#..#
+
+#..#.
+#....
+##..#
+..#..
+..###
diff --git a/2021/21/code.tl b/2021/21/code.tl
new file mode 100644
index 0000000..3622b02
--- /dev/null
+++ b/2021/21/code.tl
@@ -0,0 +1,52 @@
+(defstruct player ()
+  num
+  pos
+  (val 0))
+
+(defun read-input (: (name "input"))
+  (flow (file-get-lines name)
+    (keep-matches (`Player @num starting position: @pos` @1)
+      (new player num (toint num) pos (pred (toint pos))))))
+
+(defun counter (start)
+  (lambda () (pinc start)))
+
+(defun solve-one (: (name :))
+  (let ((count 0)
+        (die (counter 1)))
+    (buildn
+      (pend (read-input name))
+      (whilet ((p (del)))
+        (inc count)
+        (upd p.pos (+ [die] [die] [die]) (mod @1 10))
+        (if (>= (inc p.val (succ p.pos)) 1000)
+          (return (* count 3 (del).val)))
+        (add p)))))
+
+(defstruct game
+  players)
+
+(defun quantum-turn (ga)
+
+(defun solve-two (: (name :))
+  (let ((ga (new game players (read-input name))))
+    (
+
+
+        (die (counter 1))
+        (player-stream (repeat (read-input name))))
+    (each ((p player-stream))
+      (let ((npos (mod (+ p.pos [die die die] 10)))
+            (nval (
+      (if (>= npos 21))
+      ((
+
+
+    (buildn
+      (pend (read-input name))
+      (whilet ((p (del)))
+        (inc count)
+        (upd p.pos (+ [die] [die] [die]) (mod @1 10))
+        (if (>= (inc p.val (succ p.pos)) 21)
+          (return p))
+        (add p)))))
diff --git a/2021/21/input b/2021/21/input
new file mode 100644
index 0000000..9e88c73
--- /dev/null
+++ b/2021/21/input
@@ -0,0 +1,2 @@
+Player 1 starting position: 8
+Player 2 starting position: 7
diff --git a/2021/21/testinput b/2021/21/testinput
new file mode 100644
index 0000000..3f69194
--- /dev/null
+++ b/2021/21/testinput
@@ -0,0 +1,2 @@
+Player 1 starting position: 4
+Player 2 starting position: 8