Initial commit

2024-11-12 21:43:32 +01:00 · 2024-11-12 21:43:32 +01:00 · f242d2b0df
commit f242d2b0df
420 changed files with 62521 additions and 0 deletions
--- a/2019/.gitignore
+++ b/2019/.gitignore
@ -0,0 +1,3 @@
+*\~
+*.fasl
+compiled/
--- a/2019/README.org
+++ b/2019/README.org
@ -0,0 +1,10 @@
+* Advent of Code 2019
+
+My answers for [[https://adventofcode.com/2019][Advent of Code 2019]].
+
+Racket tests:
+
+#+begin_src sh
+  raco make **/*.rkt
+  raco test **/*.rkt
+#+end_src
--- a/2019/day01/day01.dyalog
+++ b/2019/day01/day01.dyalog
@ -0,0 +1,4 @@
+p←⍎¨⊃⎕nget'input.txt'1
+f←{0⌈⌊2-⍨⍵÷3}
+/f p ⍝ part 1
+/,↑{(f⍣⍵)p}¨⍳10 ⍝ part 2
--- a/2019/day01/day01.lisp
+++ b/2019/day01/day01.lisp
@ -0,0 +1,16 @@
+(defparameter *input-file* #P"input.txt")
+(defparameter *input* (uiop:read-file-lines *input-file*))
+
+(defun part1 ()
+  (loop for line in *input*
+     sum (- (floor (/ (parse-integer line) 3)) 2)))
+
+(defun total-fuel-requirements (total-fuel fuel)
+  (let ((new-fuel (max 0 (- (floor (/ fuel 3)) 2))))
+    (if (= new-fuel 0)
+	(+ total-fuel fuel)
+	(total-fuel-requirements (+ total-fuel fuel) new-fuel))))
+
+(defun part2 ()
+  (loop for line in *input*
+     sum (total-fuel-requirements 0 (- (floor (/ (parse-integer line) 3)) 2))))
--- a/2019/day01/input.txt
+++ b/2019/day01/input.txt
@ -0,0 +1,100 @@
+120847
+60347
+63340
+72773
+57020
+133960
+98163
+121548
+87233
+59150
+59712
+146816
+93205
+61936
+75319
+141998
+97125
+73450
+106250
+129939
+94854
+113782
+112044
+127923
+67114
+119770
+130034
+70876
+82204
+101939
+132604
+142836
+117066
+95861
+75597
+94630
+50085
+101107
+77937
+94286
+74091
+140875
+118543
+52767
+54544
+93062
+115681
+142065
+111737
+131214
+75160
+115432
+140504
+115376
+86589
+104631
+133012
+108690
+85993
+99533
+133725
+87698
+133480
+68379
+107852
+111209
+116623
+98717
+130227
+114356
+144516
+89663
+118355
+77816
+149914
+105080
+116793
+65259
+143900
+67838
+148389
+129753
+140524
+90005
+147305
+118428
+79940
+59110
+78120
+87066
+64722
+142066
+81410
+106958
+92984
+95584
+108534
+66362
+126340
+143660
--- a/2019/day02/day02.dyalog
+++ b/2019/day02/day02.dyalog
@ -0,0 +1,5 @@
+ ⎕io←0
+ p←⍎¨','(≠⊆⊢)⊃⊃⎕nget'input.txt'1
+ f←{i←0 ⊣ s[1 2]←⍵ ⊣ s←p ⋄ ⊃s⊣{i+←4 ⊣ a x y z←s[i+⍳4] ⋄ s[z]←(a-1)⌷s[x](+,×)s[y]}⍣{99=i⌷s}0}
+ f 12 2 ⍝ part 1
+ nv←1+,⍳99 99 ⋄ +/100 1×⊃nv[(19690720=f¨nv)⍳1] ⍝ part 2
--- a/2019/day02/day02.lisp
+++ b/2019/day02/day02.lisp
@ -0,0 +1,32 @@
+(ql:quickload "str")
+
+(defparameter *input-file* #P"input.txt")
+(defparameter *input* (uiop:read-file-string *input-file*))
+
+(defun execute (program)
+  (loop for i from 0 by 4 until (= 99 (aref program i))
+     do (let ((opcode (aref program i)))
+	  (cond ((= opcode 1)
+		 (setf (aref program (aref program (+ 3 i)))
+		       (+ (aref program (aref program (+ 1 i)))
+			  (aref program (aref program (+ 2 i))))))
+		((= opcode 2)
+		 (setf (aref program (aref program (+ 3 i)))
+		       (* (aref program (aref program (+ 1 i)))
+			  (aref program (aref program (+ 2 i)))))))))
+  program)
+
+(defun execute-with-inputs (program-string noun verb)
+    (let ((program (map 'vector #'parse-integer (str:split "," program-string))))
+      (setf (aref program 1) noun)
+      (setf (aref program 2) verb)
+      (aref (execute program) 0)))
+
+(defun part1 (program-string)
+  (execute-with-inputs program-string 12 2))
+
+(defun part2 (program-string)
+  (dotimes (noun 99)
+    (dotimes (verb 99)
+      (when (= 19690720 (execute-with-inputs program-string noun verb))
+	(return-from part2 (+ (* 100 noun) verb))))))
--- a/2019/day02/day02.rkt
+++ b/2019/day02/day02.rkt
@ -0,0 +1,34 @@
+#lang racket/base
+
+(require "../intcode.rkt"
+         racket/vector)
+
+(module+ test
+  (require rackunit))
+
+(define (part1 filename)
+  (define program (parse-file filename))
+  (vector-set! program 1 12)
+  (vector-set! program 2 2)
+  (define vm (execute (start-machine program '())))
+  (vector-ref (machine-program vm) 0))
+
+(module+ test
+  (check-equal? (part1 "input.txt") 6627023))
+
+(define (try-inputs program noun verb)
+  (define my-program (vector-copy program))
+  (vector-set! my-program 1 noun)
+  (vector-set! my-program 2 verb)
+  (define vm (execute (start-machine my-program '())))
+  (vector-ref (machine-program vm) 0))
+
+(define (part2 filename)
+  (define program (parse-file filename))
+  (for*/first ([noun (in-range 100)]
+               [verb (in-range 100)]
+               #:when (eq? 19690720 (try-inputs program noun verb)))
+    (+ (* 100 noun) verb)))
+
+(module+ test
+  (check-equal? (part2 "input.txt") 4019))
--- a/2019/day02/input.txt
+++ b/2019/day02/input.txt
@ -0,0 +1 @@
+1,0,0,3,1,1,2,3,1,3,4,3,1,5,0,3,2,9,1,19,1,9,19,23,1,23,5,27,2,27,10,31,1,6,31,35,1,6,35,39,2,9,39,43,1,6,43,47,1,47,5,51,1,51,13,55,1,55,13,59,1,59,5,63,2,63,6,67,1,5,67,71,1,71,13,75,1,10,75,79,2,79,6,83,2,9,83,87,1,5,87,91,1,91,5,95,2,9,95,99,1,6,99,103,1,9,103,107,2,9,107,111,1,111,6,115,2,9,115,119,1,119,6,123,1,123,9,127,2,127,13,131,1,131,9,135,1,10,135,139,2,139,10,143,1,143,5,147,2,147,6,151,1,151,5,155,1,2,155,159,1,6,159,0,99,2,0,14,0
--- a/2019/day03/day03.dyalog
+++ b/2019/day03/day03.dyalog
@ -0,0 +1,7 @@
+ ⎕io←0
+ p←','(≠⊆⊢)¨⊃⎕nget'input.txt'1
+ segment←{x y←⍺ ⋄ 'R'=⊃⍵:{x y+⍵}¨1↓,⍳(1+⍎1↓⍵),1 ⋄ 'L'=⊃⍵:{x y+⍵}¨1↓,-⍳(1+⍎1↓⍵),1 ⋄ 'D'=⊃⍵:{x y+⍵}¨1↓,-⍳1,1+⍎1↓⍵ ⋄ 'U'=⊃⍵:{x y+⍵}¨1↓,⍳1,1+⍎1↓⍵}
+ path←{x←⊂0 0 ⋄ 1↓x⊣{x,←(⊃⌽x) segment ⍵}¨⍵}
+ ⌊/+/↑(path ⊃0⌷p) ∩ path ⊃1⌷p ⍝ part 1
+ c←(path ⊃0⌷p)∩path ⊃1⌷p
+ 2+⌊/((path ⊃0⌷p)⍳c)+(path ⊃1⌷p)⍳c ⍝ part 2
--- a/2019/day03/input.txt
+++ b/2019/day03/input.txt
@ -0,0 +1,2 @@
+R990,U803,R777,U157,R629,D493,R498,D606,R344,U241,L708,D403,R943,U961,L107,D755,R145,D77,L654,D297,L263,D904,R405,U676,R674,U139,L746,U935,R186,U433,L739,D774,R470,D459,R865,D209,L217,U525,R747,D218,R432,U769,L876,D477,R606,D161,R991,D338,R647,D958,R777,D148,R593,D873,L95,U707,R468,U518,R845,U285,R221,U771,R989,D107,R44,U833,L343,D420,R468,D954,L604,D270,L691,U401,R850,U70,R441,U461,R638,D743,R65,U673,L999,U110,R266,U759,R768,U569,L250,D577,R247,U420,L227,U437,L80,D647,L778,U935,R585,U35,L735,D201,R694,U635,L597,U215,R743,D542,L701,U946,L503,U589,R836,D687,L444,U409,L473,U132,L570,U374,R193,D908,L800,U294,L252,U851,R947,D647,L37,D20,L27,U620,L534,D356,L291,U611,L128,D670,L364,U200,L749,D708,R776,U99,R606,D999,L810,D373,R212,D138,R856,D966,L206,D23,L860,D731,L914,U716,L212,U225,R766,U348,L220,D69,L766,D15,L557,U71,R734,D295,R884,D822,R300,D152,L986,D170,R764,U24,R394,D710,L860,U830,L305,U431,R201,D44,R882,U667,R37,D727,R916,U460,L834,D771,R373,U96,L707,D576,R607,D351,R577,D200,L402,U364,L32,D512,L152,D283,L232,U804,R827,U352,R104,D323,L254,U273,L451,D967,R739,D53,L908,D866,R998,U897,L581,U538,R206,U644,L70,D17,L481,U912,L377,D922,L286,U547,R35,U292,L318,U256,R79,D52,R92,U160,R763,U428,R663,D634,R212,D325,R460,U142,L375,U382,R20,D321,L220,D578,R915,D465,L797,D849,L281,D491,L911,D624,R800,U629,L675,U428,L219,U694,R680,U350,R113,D903,L22,D683,L787,D1,R93,U315,L562,U756,R622,D533,L587,D216,L933,U972,R506,U536,R797,U828,L12,D965,L641,U165,R937,D675,R259
+L998,D197,L301,D874,L221,U985,L213,D288,R142,D635,R333,D328,R405,D988,L23,D917,R412,D971,R876,U527,R987,D884,R39,D485,L971,U200,R931,U79,L271,U183,R354,D18,R346,D866,L752,D204,L863,U784,R292,U676,R811,U721,L53,U983,L993,U822,R871,U539,L782,D749,R417,U667,R882,U467,R321,U894,R912,U756,L102,U154,L57,D316,R200,U372,L44,U406,L426,D613,R847,U977,R303,U469,R509,U839,L633,D267,L487,D976,R325,U399,L359,U161,L305,U935,R522,D848,R784,D273,L337,D55,L266,U406,L858,D650,L176,D124,R231,U513,L462,U328,L674,D598,R568,D742,L39,D438,L643,D254,R577,U519,R325,U124,R91,U129,L79,D52,R480,D46,R129,D997,R452,D992,L721,U490,L595,D666,R372,D198,R813,U624,L469,U59,R578,U184,R117,D749,L745,U302,R398,D951,L683,D360,R476,D788,R70,U693,R295,D547,L61,U782,R440,D818,L330,D321,L968,U622,R160,U571,L886,D43,L855,U272,R530,D267,L312,D519,L741,D697,R206,U148,L445,U857,R983,D192,L788,U826,R805,U932,R888,D250,L682,D52,R406,D176,R984,D637,L947,D416,L687,U699,L544,D710,L933,D171,L357,D134,L968,D538,R496,D240,L730,U771,R554,U708,R265,D748,L839,U668,L333,U335,R526,U809,L653,D6,R234,D130,R871,U911,R538,U372,L960,D535,L196,U236,L966,D185,L166,U789,L885,U453,R627,D586,R501,U222,L280,U124,R755,D159,L759,U78,R669,D889,L150,D888,L71,D917,L126,D97,L138,U726,R160,D971,R527,D988,R455,D413,R539,U923,R258,U734,L459,D954,R877,U613,R343,D98,R238,U478,R514,U814,L274,U119,L958,U698,R761,U693,R367,D111,L800,D531,L91,U616,R208,D255,R169,U145,R671,U969,L468,U566,R589,D455,R323,D303,R374,D890,R377,D262,L40,U85,L719
--- a/2019/day04/day04.dyalog
+++ b/2019/day04/day04.dyalog
@ -0,0 +1,14 @@
+ ⎕io←0
+ a b←245182 790572
+ p←⊃(,(∘.,))/6/⊂⍳10
+ x←{(1↓⍵)-¯1↓⍵}¨p
+ n←10⊥¨((∨/¨0=x)∧∧/¨0≤x)/p
+ ≢((n>a)∧n<b)/n ⍝ part 1
+ n2←10⊥¨(({∨/2=⍵}¨(⊢∘≢⌸)¨p)∧∧/¨0≤x)/p
+ ≢((n2>a)∧n2<b)/n2 ⍝ part 2
+
+ ⍝ better version (inspired from
+ ⍝ https://github.com/jayfoad/aoc2019apl/blob/master/p4.dyalog)
+ p←⍉10⊥⍣¯1⊢a+⍳1+b-a
+ +/({∧/2≤/⍵}∧{∨/2=/⍵})p ⍝ part 1
+ +/({∧/2≤/⍵}∧{∨/¨2=(⊢∘≢⌸)¨↓⍵})p ⍝ part 2
--- a/2019/day05/day05.lisp
+++ b/2019/day05/day05.lisp
@ -0,0 +1,61 @@
+(defparameter *input-file* #P"input.txt")
+(defparameter *input* (uiop:read-file-string *input-file*))
+
+(defvar *program*)
+
+(defun opcode (pc)
+  (mod (aref *program* pc) 100))
+
+(defun parameter-mode (pc index)
+  (mod (truncate (aref *program* pc) (expt 10 (+ 1 index))) 10))
+
+(defun parameter (pc index)
+  (ecase (parameter-mode pc index)
+    (1 (aref *program* (+ index pc)))
+    (0 (aref *program* (aref *program* (+ pc index))))))
+
+(defun (setf parameter) (new-value pc index)
+  (ecase (parameter-mode pc index)
+    (0 (setf (aref *program* (aref *program* (+ pc index))) new-value))
+    (1 (error "Cannot write with a parameter in immediate mode"))))
+
+(defun execute (inputs)
+  (defun execute-instruction (pc inputs outputs)
+    (ecase (opcode pc)
+      (99 (return-from execute-instruction outputs))
+      (1 (setf (parameter pc 3) (+ (parameter pc 1) (parameter pc 2)))
+	 (execute-instruction (+ pc 4) inputs outputs))
+      (2 (setf (parameter pc 3) (* (parameter pc 1) (parameter pc 2)))
+	 (execute-instruction (+ pc 4) inputs outputs))
+      (3 (setf (parameter pc 1) (car inputs))
+	 (execute-instruction (+ pc 2) (cdr inputs) outputs))
+      (4 (execute-instruction (+ pc 2) inputs (cons (parameter pc 1) outputs)))
+      (5 (if (/= 0 (parameter pc 1))
+	     (execute-instruction (parameter pc 2) inputs outputs)
+	     (execute-instruction (+ pc 3) inputs outputs)))
+      (6 (if (= 0 (parameter pc 1))
+	     (execute-instruction (parameter pc 2) inputs outputs)
+	     (execute-instruction (+ pc 3) inputs outputs)))
+      (7 (if (< (parameter pc 1) (parameter pc 2))
+	     (setf (parameter pc 3) 1)
+	     (setf (parameter pc 3) 0))
+	 (execute-instruction (+ pc 4) inputs outputs))
+      (8 (if (= (parameter pc 1) (parameter pc 2))
+	     (setf (parameter pc 3) 1)
+	     (setf (parameter pc 3) 0))
+	 (execute-instruction (+ pc 4) inputs outputs))))
+  (execute-instruction 0 inputs nil))
+
+(defun parse-program (program-string)
+  (map 'vector #'parse-integer (uiop:split-string program-string :separator ",")))
+
+(defun part1 ()
+  (let ((*program* (parse-program *input*)))
+    (car (execute '(1)))))
+
+(defun part2 ()
+  (let ((*program* (parse-program *input*)))
+    (car (execute '(5)))))
+
+(assert (= (part1) 12896948))
+(assert (= (part2) 7704130))
--- a/2019/day05/day05.rkt
+++ b/2019/day05/day05.rkt
@ -0,0 +1,22 @@
+#lang racket/base
+
+(require "../intcode.rkt")
+
+(module+ test
+  (require rackunit))
+
+(define (part1 filename)
+  (define program (parse-file filename))
+  (define vm (execute (start-machine program '(1))))
+  (car (machine-outputs vm)))
+
+(module+ test
+  (check-equal? (part1 "input.txt") 12896948))
+
+(define (part2 filename)
+  (define program (parse-file filename))
+  (define vm (execute (start-machine program '(5))))
+  (car (machine-outputs vm)))
+
+(module+ test
+  (check-equal? (part2 "input.txt") 7704130))
--- a/2019/day05/input.txt
+++ b/2019/day05/input.txt
@ -0,0 +1 @@
+3,225,1,225,6,6,1100,1,238,225,104,0,1102,46,47,225,2,122,130,224,101,-1998,224,224,4,224,1002,223,8,223,1001,224,6,224,1,224,223,223,1102,61,51,225,102,32,92,224,101,-800,224,224,4,224,1002,223,8,223,1001,224,1,224,1,223,224,223,1101,61,64,225,1001,118,25,224,101,-106,224,224,4,224,1002,223,8,223,101,1,224,224,1,224,223,223,1102,33,25,225,1102,73,67,224,101,-4891,224,224,4,224,1002,223,8,223,1001,224,4,224,1,224,223,223,1101,14,81,225,1102,17,74,225,1102,52,67,225,1101,94,27,225,101,71,39,224,101,-132,224,224,4,224,1002,223,8,223,101,5,224,224,1,224,223,223,1002,14,38,224,101,-1786,224,224,4,224,102,8,223,223,1001,224,2,224,1,223,224,223,1,65,126,224,1001,224,-128,224,4,224,1002,223,8,223,101,6,224,224,1,224,223,223,1101,81,40,224,1001,224,-121,224,4,224,102,8,223,223,101,4,224,224,1,223,224,223,4,223,99,0,0,0,677,0,0,0,0,0,0,0,0,0,0,0,1105,0,99999,1105,227,247,1105,1,99999,1005,227,99999,1005,0,256,1105,1,99999,1106,227,99999,1106,0,265,1105,1,99999,1006,0,99999,1006,227,274,1105,1,99999,1105,1,280,1105,1,99999,1,225,225,225,1101,294,0,0,105,1,0,1105,1,99999,1106,0,300,1105,1,99999,1,225,225,225,1101,314,0,0,106,0,0,1105,1,99999,1008,677,226,224,1002,223,2,223,1005,224,329,1001,223,1,223,107,677,677,224,102,2,223,223,1005,224,344,101,1,223,223,1107,677,677,224,102,2,223,223,1005,224,359,1001,223,1,223,1108,226,226,224,1002,223,2,223,1006,224,374,101,1,223,223,107,226,226,224,1002,223,2,223,1005,224,389,1001,223,1,223,108,226,226,224,1002,223,2,223,1005,224,404,1001,223,1,223,1008,677,677,224,1002,223,2,223,1006,224,419,1001,223,1,223,1107,677,226,224,102,2,223,223,1005,224,434,1001,223,1,223,108,226,677,224,102,2,223,223,1006,224,449,1001,223,1,223,8,677,226,224,102,2,223,223,1006,224,464,1001,223,1,223,1007,677,226,224,1002,223,2,223,1006,224,479,1001,223,1,223,1007,677,677,224,1002,223,2,223,1005,224,494,1001,223,1,223,1107,226,677,224,1002,223,2,223,1006,224,509,101,1,223,223,1108,226,677,224,102,2,223,223,1005,224,524,1001,223,1,223,7,226,226,224,102,2,223,223,1005,224,539,1001,223,1,223,8,677,677,224,1002,223,2,223,1005,224,554,101,1,223,223,107,677,226,224,102,2,223,223,1006,224,569,1001,223,1,223,7,226,677,224,1002,223,2,223,1005,224,584,1001,223,1,223,1008,226,226,224,1002,223,2,223,1006,224,599,101,1,223,223,1108,677,226,224,102,2,223,223,1006,224,614,101,1,223,223,7,677,226,224,102,2,223,223,1005,224,629,1001,223,1,223,8,226,677,224,1002,223,2,223,1006,224,644,101,1,223,223,1007,226,226,224,102,2,223,223,1005,224,659,101,1,223,223,108,677,677,224,1002,223,2,223,1006,224,674,1001,223,1,223,4,223,99,226
--- a/2019/day06/day06.rkt
+++ b/2019/day06/day06.rkt
@ -0,0 +1,23 @@
+#lang racket
+
+(require racket/string
+         graph)
+
+(define (read-graph filename)
+  (with-input-from-file filename
+    (lambda ()
+     (define g (unweighted-graph/directed '()))
+     (for ([line (in-lines)])
+       (define bodies (string-split line ")"))
+       (add-edge! g (car bodies) (cadr bodies)))
+     g)))
+
+(define (part1 filename)
+  (define g (read-graph filename))
+  (define-values (dists _) (bfs g "COM"))
+  (for/sum ([i (in-hash-values dists)]) i))
+
+(define (part2 filename)
+  (define g (read-graph filename))
+  (define-values (dists _) (bfs g "YOU"))
+  (- (hash-ref dists "SAN") 2))
--- a/2019/day06/input
+++ b/2019/day06/input
--- a/2019/day06/test
+++ b/2019/day06/test
@ -0,0 +1,11 @@
+COM)B
+B)C
+C)D
+D)E
+E)F
+B)G
+G)H
+D)I
+E)J
+J)K
+K)L
--- a/2019/day06/test2
+++ b/2019/day06/test2
@ -0,0 +1,13 @@
+COM)B
+B)C
+C)D
+D)E
+E)F
+B)G
+G)H
+D)I
+E)J
+J)K
+K)L
+K)YOU
+I)SAN
--- a/2019/day07/day07.lisp
+++ b/2019/day07/day07.lisp
@ -0,0 +1,87 @@
+(ql:quickload :alexandria)
+
+(defparameter *input-file* #P"input.txt")
+(defvar *input*)
+
+(defvar *program*)
+(defvar *input-fn*)
+(defvar *output-fn*)
+
+(defun opcode (pc)
+  (mod (aref *program* pc) 100))
+
+(defun parameter-mode (pc index)
+  (mod (truncate (aref *program* pc) (expt 10 (+ 1 index))) 10))
+
+(defun parameter (pc index)
+  (ecase (parameter-mode pc index)
+    (1 (aref *program* (+ index pc)))
+    (0 (aref *program* (aref *program* (+ pc index))))))
+
+(defun (setf parameter) (new-value pc index)
+  (ecase (parameter-mode pc index)
+    (0 (setf (aref *program* (aref *program* (+ pc index))) new-value))
+    (1 (error "Cannot write with a parameter in immediate mode"))))
+
+(defun execute-instruction (pc)
+  (ecase (opcode pc)
+    (99 (return-from execute-instruction))
+    (1 (setf (parameter pc 3) (+ (parameter pc 1) (parameter pc 2)))
+       (execute-instruction (+ pc 4)))
+    (2 (setf (parameter pc 3) (* (parameter pc 1) (parameter pc 2)))
+       (execute-instruction (+ pc 4)))
+    (3 (setf (parameter pc 1) (funcall *input-fn*))
+       (execute-instruction (+ pc 2)))
+    (4  (funcall *output-fn* (parameter pc 1))
+	(execute-instruction (+ pc 2)))
+    (5 (if (/= 0 (parameter pc 1))
+	   (execute-instruction (parameter pc 2))
+	   (execute-instruction (+ pc 3))))
+    (6 (if (= 0 (parameter pc 1))
+	   (execute-instruction (parameter pc 2))
+	   (execute-instruction (+ pc 3))))
+    (7 (if (< (parameter pc 1) (parameter pc 2))
+	   (setf (parameter pc 3) 1)
+	   (setf (parameter pc 3) 0))
+       (execute-instruction (+ pc 4)))
+    (8 (if (= (parameter pc 1) (parameter pc 2))
+	   (setf (parameter pc 3) 1)
+	   (setf (parameter pc 3) 0))
+       (execute-instruction (+ pc 4)))))
+
+(defun execute (program &key (input 'input) (output 'output))
+  (let ((*program* program)
+	(*input-fn* input)
+	(*output-fn* output))
+    (execute-instruction 0)))
+
+(defun parse-program (program-string)
+  (map 'vector #'parse-integer (uiop:split-string program-string :separator ",")))
+
+(defun amplify (phases)
+  (let ((amp-input 0))
+    (loop for phase in phases
+       do (let ((program (alexandria:copy-array *program*))
+		(inputs (list phase amp-input))
+		(output nil))
+	    (execute program :input (lambda () (pop inputs)) :output (lambda (x) (setf output x)))
+	    (setf amp-input output)))
+    amp-input))
+
+(defun max-thrust ()
+  (let ((res nil))
+    (alexandria:map-permutations (lambda (x) (push (amplify x) res)) '(0 1 2 3 4))
+    (apply #'max res)))
+
+(assert (= 43210 (let ((*program* (parse-program "3,15,3,16,1002,16,10,16,1,16,15,15,4,15,99,0,0")))
+		   (max-thrust))))
+
+(assert (= 54321 (let ((*program* (parse-program "3,23,3,24,1002,24,10,24,1002,23,-1,23,101,5,23,23,1,24,23,23,4,23,99,0,0")))
+		   (max-thrust))))
+
+(assert (= 65210 (let ((*program* (parse-program "3,31,3,32,1002,32,10,32,1001,31,-2,31,1007,31,0,33,1002,33,7,33,1,33,31,31,1,32,31,31,4,31,99,0,0,0")))
+		   (max-thrust))))
+
+(defun part1 ()
+  (let ((*program* (parse-program (uiop:read-file-string *input-file*))))
+    (max-thrust)))
--- a/2019/day07/day07.rkt
+++ b/2019/day07/day07.rkt
@ -0,0 +1,51 @@
+#lang racket/base
+
+(require "../intcode.rkt"
+         racket/list)
+
+(module+ test
+  (require rackunit))
+
+(define (part1 program)
+  (apply max
+         (for/list ([phases (in-permutations (range 5))])
+           (for/fold ([signal 0])
+                     ([phase (in-list phases)])
+             (define vm (execute (start-machine program (list phase signal))))
+             (car (machine-outputs vm))))))
+
+(module+ test
+  (check-equal? (part1 (parse "3,15,3,16,1002,16,10,16,1,16,15,15,4,15,99,0,0")) 43210)
+  (check-equal? (part1 (parse "3,23,3,24,1002,24,10,24,1002,23,-1,23,
+101,5,23,23,1,24,23,23,4,23,99,0,0")) 54321)
+  (check-equal? (part1 (parse "3,31,3,32,1002,32,10,32,1001,31,-2,31,1007,31,0,33,
+1002,33,7,33,1,33,31,31,1,32,31,31,4,31,99,0,0,0")) 65210)
+  (check-equal? (part1 (parse-file "input.txt")) 298586))
+
+(define (part2 program)
+  (define signals
+    (for/list ([phases (in-permutations (range 5 10))])
+      (define amplifiers
+        (for/list ([phase (in-list phases)])
+          (define vm (execute (start-machine program (list phase))))
+          vm))
+      (let loop ([signal 0]
+                 [amplifiers amplifiers])
+        (if (empty? amplifiers)
+            signal
+            (let* ([amp (machine-program (car amplifiers))]
+                   [pc (machine-pc (car amplifiers))]
+                   [new-vm (execute (machine amp (list signal) pc 0 #f '()))]
+                   [new-amplifiers (if (machine-terminated new-vm)
+                                       (cdr amplifiers)
+                                       (append (cdr amplifiers) (list new-vm)))])
+              (loop (car (machine-outputs new-vm)) new-amplifiers))))))
+  (apply max signals))
+
+(module+ test
+  (check-equal? (part2 (parse "3,26,1001,26,-4,26,3,27,1002,27,2,27,1,27,26,
+27,4,27,1001,28,-1,28,1005,28,6,99,0,0,5")) 139629729)
+  (check-equal? (part2 (parse "3,52,1001,52,-5,52,3,53,1,52,56,54,1007,54,5,55,1005,55,26,1001,54,
+-5,54,1105,1,12,1,53,54,53,1008,54,0,55,1001,55,1,55,2,53,55,53,4,
+53,1001,56,-1,56,1005,56,6,99,0,0,0,0,10")) 18216)
+  (check-equal? (part2 (parse-file "input.txt")) 9246095))
--- a/2019/day07/input.txt
+++ b/2019/day07/input.txt
@ -0,0 +1 @@
+3,8,1001,8,10,8,105,1,0,0,21,42,67,84,109,126,207,288,369,450,99999,3,9,102,4,9,9,1001,9,4,9,102,2,9,9,101,2,9,9,4,9,99,3,9,1001,9,5,9,1002,9,5,9,1001,9,5,9,1002,9,5,9,101,5,9,9,4,9,99,3,9,101,5,9,9,1002,9,3,9,1001,9,2,9,4,9,99,3,9,1001,9,2,9,102,4,9,9,101,2,9,9,102,4,9,9,1001,9,2,9,4,9,99,3,9,102,2,9,9,101,5,9,9,1002,9,2,9,4,9,99,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,101,2,9,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,1,9,4,9,99,3,9,1001,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,99,3,9,102,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,1,9,9,4,9,3,9,101,1,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,101,2,9,9,4,9,3,9,101,1,9,9,4,9,3,9,101,1,9,9,4,9,3,9,101,2,9,9,4,9,99,3,9,1001,9,2,9,4,9,3,9,101,1,9,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,1001,9,2,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,1,9,9,4,9,3,9,102,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,101,1,9,9,4,9,99,3,9,102,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,2,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,1002,9,2,9,4,9,3,9,101,1,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,99
--- a/2019/day08/day08.dyalog
+++ b/2019/day08/day08.dyalog
@ -0,0 +1,4 @@
+ p←100 6 25⍴⍎¨⊃⊃⎕nget'input.txt'1
+ x←,(⊃⍋+/+/0=p)⌷p
+ (+/1=x)×+/2=x ⍝ part 1
+ ' ⌺'[{1⌷⍋⍵⍳0 1}¨⊂[1]p] ⍝ part 2
--- a/2019/day08/input.txt
+++ b/2019/day08/input.txt
--- a/2019/day09/day09.rkt
+++ b/2019/day09/day09.rkt
@ -0,0 +1,29 @@
+#lang racket/base
+
+(require "../intcode.rkt")
+
+(module+ test
+  (require rackunit))
+
+(define (part12 program input)
+  (define vm (execute (start-machine program (list input))))
+  (car (machine-outputs vm)))
+
+(module+ test
+  (test-case "quine"
+    (define quine (parse "109,1,204,-1,1001,100,1,100,1008,100,16,101,1006,101,0,99"))
+    (define vm (execute (start-machine quine '())))
+    (check-true (machine-terminated vm))
+    (check-equal? (reverse (machine-outputs vm)) (vector->list quine)))
+  (test-case "16-digit number"
+    (define program (parse "1102,34915192,34915192,7,4,7,99,0"))
+    (define vm (execute (start-machine program '())))
+    (check-true (machine-terminated vm))
+    (check-equal? (string-length (number->string (car (machine-outputs vm)))) 16))
+  (test-case "large number"
+    (define program (parse "104,1125899906842624,99"))
+    (define vm (execute (start-machine program '())))
+    (check-true (machine-terminated vm))
+    (check-equal? (car (machine-outputs vm)) 1125899906842624))
+  (check-equal? (part12 (parse-file "input") 1) 3601950151)
+  (check-equal? (part12 (parse-file "input") 2) 64236))
--- a/2019/day09/input
+++ b/2019/day09/input
@ -0,0 +1 @@
+1102,34463338,34463338,63,1007,63,34463338,63,1005,63,53,1101,0,3,1000,109,988,209,12,9,1000,209,6,209,3,203,0,1008,1000,1,63,1005,63,65,1008,1000,2,63,1005,63,904,1008,1000,0,63,1005,63,58,4,25,104,0,99,4,0,104,0,99,4,17,104,0,99,0,0,1101,0,30,1016,1101,37,0,1005,1101,362,0,1023,1101,0,20,1014,1101,39,0,1013,1102,34,1,1007,1101,682,0,1027,1102,664,1,1025,1102,1,655,1028,1101,0,26,1002,1102,1,38,1015,1101,669,0,1024,1101,0,28,1017,1102,1,21,1000,1101,0,27,1012,1102,1,29,1008,1102,1,23,1019,1101,0,24,1011,1101,685,0,1026,1102,646,1,1029,1102,1,369,1022,1101,0,31,1003,1102,1,36,1001,1101,0,0,1020,1102,1,35,1009,1101,32,0,1010,1101,0,1,1021,1102,33,1,1004,1101,22,0,1006,1102,1,25,1018,109,14,1205,6,197,1001,64,1,64,1105,1,199,4,187,1002,64,2,64,109,-4,21107,40,39,9,1005,1019,219,1001,64,1,64,1105,1,221,4,205,1002,64,2,64,109,9,1206,1,239,4,227,1001,64,1,64,1106,0,239,1002,64,2,64,109,-9,2101,0,-8,63,1008,63,26,63,1005,63,261,4,245,1106,0,265,1001,64,1,64,1002,64,2,64,109,-6,2108,37,1,63,1005,63,287,4,271,1001,64,1,64,1105,1,287,1002,64,2,64,109,15,21108,41,44,-2,1005,1017,307,1001,64,1,64,1106,0,309,4,293,1002,64,2,64,109,-16,1207,1,34,63,1005,63,327,4,315,1105,1,331,1001,64,1,64,1002,64,2,64,109,8,1208,-9,29,63,1005,63,347,1106,0,353,4,337,1001,64,1,64,1002,64,2,64,109,4,2105,1,8,1001,64,1,64,1105,1,371,4,359,1002,64,2,64,109,-22,1201,9,0,63,1008,63,27,63,1005,63,391,1106,0,397,4,377,1001,64,1,64,1002,64,2,64,109,18,21107,42,43,5,1005,1016,415,4,403,1106,0,419,1001,64,1,64,1002,64,2,64,109,-8,1201,2,0,63,1008,63,37,63,1005,63,441,4,425,1105,1,445,1001,64,1,64,1002,64,2,64,109,27,1205,-9,463,4,451,1001,64,1,64,1106,0,463,1002,64,2,64,109,-1,1206,-8,475,1105,1,481,4,469,1001,64,1,64,1002,64,2,64,109,-6,21101,43,0,-8,1008,1015,43,63,1005,63,507,4,487,1001,64,1,64,1106,0,507,1002,64,2,64,109,-15,2101,0,-3,63,1008,63,35,63,1005,63,531,1001,64,1,64,1106,0,533,4,513,1002,64,2,64,109,-2,2102,1,-6,63,1008,63,18,63,1005,63,553,1105,1,559,4,539,1001,64,1,64,1002,64,2,64,109,7,21102,44,1,3,1008,1016,44,63,1005,63,581,4,565,1105,1,585,1001,64,1,64,1002,64,2,64,109,-11,1202,7,1,63,1008,63,34,63,1005,63,609,1001,64,1,64,1105,1,611,4,591,1002,64,2,64,109,6,1202,1,1,63,1008,63,35,63,1005,63,637,4,617,1001,64,1,64,1106,0,637,1002,64,2,64,109,16,2106,0,4,4,643,1001,64,1,64,1106,0,655,1002,64,2,64,109,-1,2105,1,1,4,661,1106,0,673,1001,64,1,64,1002,64,2,64,109,5,2106,0,-1,1105,1,691,4,679,1001,64,1,64,1002,64,2,64,109,-24,1208,-2,26,63,1005,63,709,4,697,1105,1,713,1001,64,1,64,1002,64,2,64,109,-10,2102,1,6,63,1008,63,21,63,1005,63,735,4,719,1105,1,739,1001,64,1,64,1002,64,2,64,109,25,21108,45,45,-9,1005,1010,757,4,745,1106,0,761,1001,64,1,64,1002,64,2,64,109,-12,1207,-7,20,63,1005,63,777,1106,0,783,4,767,1001,64,1,64,1002,64,2,64,109,-13,2108,22,6,63,1005,63,799,1106,0,805,4,789,1001,64,1,64,1002,64,2,64,109,17,21102,46,1,0,1008,1011,45,63,1005,63,825,1105,1,831,4,811,1001,64,1,64,1002,64,2,64,109,-6,2107,21,1,63,1005,63,849,4,837,1105,1,853,1001,64,1,64,1002,64,2,64,109,-3,2107,27,0,63,1005,63,873,1001,64,1,64,1105,1,875,4,859,1002,64,2,64,109,12,21101,47,0,0,1008,1014,48,63,1005,63,899,1001,64,1,64,1105,1,901,4,881,4,64,99,21102,27,1,1,21101,0,915,0,1105,1,922,21201,1,42931,1,204,1,99,109,3,1207,-2,3,63,1005,63,964,21201,-2,-1,1,21101,942,0,0,1106,0,922,21202,1,1,-1,21201,-2,-3,1,21102,1,957,0,1106,0,922,22201,1,-1,-2,1106,0,968,22101,0,-2,-2,109,-3,2106,0,0
--- a/2019/day10/day10.rkt
+++ b/2019/day10/day10.rkt
@ -0,0 +1,87 @@
+#lang racket
+
+(module+ test
+  (require rackunit))
+
+(define (read-input filename)
+  (string->grid (file->string filename)))
+
+(define (string->grid str)
+  (for/set ([line (string-split str)]
+            [i (in-naturals)]
+            #:when #t
+            [c (in-string line)]
+            [j (in-naturals)]
+            #:when (eq? c #\#))
+    (make-rectangular j i)))
+
+(define (segment->direction x)
+  (define a (real-part x))
+  (define b (imag-part x))
+  (define r (gcd a b))
+  (make-rectangular (/ a r) (/ b r)))
+
+(define (detected grid)
+  (for/hash ([x (in-set grid)])
+    (values x (for/set ([y (in-set grid)]
+                        #:unless (= x y))
+                (segment->direction (- y x))))))
+
+(define (find-station grid)
+  (define visible (detected grid))
+  (define max-visible (apply max (map set-count (hash-values visible))))
+  (define pos (for/first ([(k v) (in-hash visible)]
+                      #:when (= max-visible (set-count v)))
+                k))
+  (values pos (hash-ref visible pos)))
+
+(define (part1 filename)
+  (define grid (read-input filename))
+  (define-values (loc dirs) (find-station grid))
+  (set-count dirs))
+
+(module+ test
+  (check-equal? (part1 "test") 8)
+  (check-equal? (part1 "input") 286))
+
+(define (find-target grid station direction)
+  (define targets
+    (for/list ([x (in-set grid)]
+               #:unless (= x station)
+               #:when (real? (/ (- x station) direction))
+               #:when (<= 0 (/ (- x station) direction)))
+      x))
+  (car (sort targets
+             (λ (x y) (< (magnitude (- x station))
+                         (magnitude (- y station)))))))
+
+(define (rotate-left lst)
+  (if (empty? lst)
+      '()
+      (append (cdr lst) (list (car lst)))))
+
+(define (rotate-right lst)
+  (reverse (rotate-left (reverse lst))))
+
+(define (find-nth-target grid n)
+  (define-values (station directions) (find-station grid))
+  (define directions-sorted (rotate-right
+                             (sort (set->list directions)
+                                   (λ (x y) (< (angle (* -i x)) (angle (* -i y)))))))
+  (define-values (final-grid targets)
+    (for/fold ([grid grid]
+               [targets '()])
+              ([i (in-range n)]
+               [dir (in-cycle directions-sorted)])
+      (define target (find-target grid station dir))
+      (values (set-remove grid target)
+              (cons target targets))))
+  (car targets))
+
+(define (part2 filename)
+  (define grid (read-input filename))
+  (define target (find-nth-target grid 200))
+  (+ (* 100 (real-part target)) (imag-part target)))
+
+(module+ test
+  (check-equal? (part2 "input") 504))
--- a/2019/day10/input
+++ b/2019/day10/input
@ -0,0 +1,30 @@
+.#.####..#.#...#...##..#.#.##.
+..#####.##..#..##....#..#...#.
+......#.......##.##.#....##..#
+..#..##..#.###.....#.#..###.#.
+..#..#..##..#.#.##..###.......
+...##....#.##.#.#..##.##.#...#
+.##...#.#.##..#.#........#.#..
+.##...##.##..#.#.##.#.#.#.##.#
+#..##....#...###.#..##.#...##.
+.###.###..##......#..#...###.#
+.#..#.####.#..#....#.##..#.#.#
+..#...#..#.#######....###.....
+####..#.#.#...##...##....#..##
+##..#.##.#.#..##.###.#.##.##..
+..#.........#.#.#.#.......#..#
+...##.#.....#.#.##........#..#
+##..###.....#.............#.##
+.#...#....#..####.#.#......##.
+..#..##..###...#.....#...##..#
+...####..#.#.##..#....#.#.....
+####.#####.#.#....#.#....##.#.
+#.#..#......#.........##..#.#.
+#....##.....#........#..##.##.
+.###.##...##..#.##.#.#...#.#.#
+##.###....##....#.#.....#.###.
+..#...#......#........####..#.
+#....#.###.##.#...#.#.#.#.....
+.........##....#...#.....#..##
+###....#.........#..#..#.#.#..
+##...#...###.#..#.###....#.##.
--- a/2019/day10/test
+++ b/2019/day10/test
@ -0,0 +1,5 @@
+.#..#
+.....
+#####
+....#
+...##
--- a/2019/day11/day11.rkt
+++ b/2019/day11/day11.rkt
@ -0,0 +1,58 @@
+#lang racket/base
+
+(require "../intcode.rkt"
+         racket/set)
+
+(module+ test
+  (require rackunit))
+
+(define (part12 program start-panel [show-grid #f])
+  (define vm (execute (start-machine program '())))
+  (define grid (make-hash))
+  (hash-set! grid 0 start-panel)
+  (define painted (mutable-set))
+  (let loop ([vm vm]
+             [direction 0+1i]
+             [position 0])
+    (define new-vm
+      (execute (machine (machine-program vm)
+                        (list (hash-ref grid position 0))
+                        (machine-pc vm)
+                        (machine-relative-base vm)
+                        #f
+                        '())))
+    (unless (machine-terminated new-vm)
+      (hash-set! grid position (cadr (machine-outputs new-vm)))
+      (set-add! painted position)
+      (define new-direction (if (= 0 (car (machine-outputs new-vm)))
+                                (* direction 0+1i)
+                                (* direction 0-1i)))
+      (define new-position (+ position new-direction))
+      (loop new-vm new-direction new-position)))
+  (when show-grid
+    (display-grid grid))
+  (set-count painted))
+
+(define (display-grid grid)
+  (define min-x (apply min (map real-part (hash-keys grid))))
+  (define max-x (apply max (map real-part (hash-keys grid))))
+  (define min-y (apply min (map imag-part (hash-keys grid))))
+  (define max-y (apply max (map imag-part (hash-keys grid))))
+  (for* ([j (in-range max-y (sub1 min-y) -1)]
+         [i (in-range min-x max-x)])
+    (if (= 1 (hash-ref grid (make-rectangular i j) 0))
+        (printf "#")
+        (printf " "))
+    (when (= i (sub1 max-x))
+      (printf "\n"))))
+
+(module+ test
+  (check-equal? (part12 (parse-file "input") 0) 2511))
+
+;; > (part12 (parse-file "input") 1 #t)
+;; #  #   ## #  #   ## #  #  ##  ###  #  #                                              
+;; #  #    # # #     # # #  #  # #  # #  #                                              
+;; ####    # ##      # ##   #    #  # ####                                              
+;; #  #    # # #     # # #  # ## ###  #  #                                              
+;; #  # #  # # #  #  # # #  #  # #    #  #                                              
+;; #  #  ##  #  #  ##  #  #  ### #    #  #   
--- a/2019/day11/input
+++ b/2019/day11/input
@ -0,0 +1 @@
+3,8,1005,8,328,1106,0,11,0,0,0,104,1,104,0,3,8,1002,8,-1,10,1001,10,1,10,4,10,1008,8,0,10,4,10,1001,8,0,29,1,104,7,10,3,8,1002,8,-1,10,101,1,10,10,4,10,1008,8,0,10,4,10,1001,8,0,55,1,2,7,10,1006,0,23,3,8,102,-1,8,10,1001,10,1,10,4,10,1008,8,0,10,4,10,1001,8,0,84,1006,0,40,1,1103,14,10,1,1006,16,10,3,8,102,-1,8,10,101,1,10,10,4,10,108,1,8,10,4,10,1002,8,1,116,1006,0,53,1,1104,16,10,3,8,102,-1,8,10,101,1,10,10,4,10,1008,8,1,10,4,10,102,1,8,146,2,1104,9,10,3,8,102,-1,8,10,101,1,10,10,4,10,1008,8,1,10,4,10,1001,8,0,172,1006,0,65,1,1005,8,10,1,1002,16,10,3,8,102,-1,8,10,1001,10,1,10,4,10,108,0,8,10,4,10,102,1,8,204,2,1104,9,10,1006,0,30,3,8,102,-1,8,10,101,1,10,10,4,10,108,0,8,10,4,10,102,1,8,233,2,1109,6,10,1006,0,17,1,2,6,10,3,8,102,-1,8,10,101,1,10,10,4,10,108,1,8,10,4,10,102,1,8,266,1,106,7,10,2,109,2,10,2,9,8,10,3,8,102,-1,8,10,101,1,10,10,4,10,1008,8,1,10,4,10,1001,8,0,301,1,109,9,10,1006,0,14,101,1,9,9,1007,9,1083,10,1005,10,15,99,109,650,104,0,104,1,21102,1,837548789788,1,21101,0,345,0,1106,0,449,21101,0,846801511180,1,21101,0,356,0,1106,0,449,3,10,104,0,104,1,3,10,104,0,104,0,3,10,104,0,104,1,3,10,104,0,104,1,3,10,104,0,104,0,3,10,104,0,104,1,21101,235244981271,0,1,21101,403,0,0,1105,1,449,21102,1,206182744295,1,21101,0,414,0,1105,1,449,3,10,104,0,104,0,3,10,104,0,104,0,21102,837896937832,1,1,21101,0,437,0,1106,0,449,21101,867965862668,0,1,21102,448,1,0,1106,0,449,99,109,2,22102,1,-1,1,21101,40,0,2,21102,1,480,3,21101,0,470,0,1106,0,513,109,-2,2106,0,0,0,1,0,0,1,109,2,3,10,204,-1,1001,475,476,491,4,0,1001,475,1,475,108,4,475,10,1006,10,507,1101,0,0,475,109,-2,2106,0,0,0,109,4,1201,-1,0,512,1207,-3,0,10,1006,10,530,21102,1,0,-3,22102,1,-3,1,21201,-2,0,2,21102,1,1,3,21102,549,1,0,1106,0,554,109,-4,2105,1,0,109,5,1207,-3,1,10,1006,10,577,2207,-4,-2,10,1006,10,577,21202,-4,1,-4,1106,0,645,21202,-4,1,1,21201,-3,-1,2,21202,-2,2,3,21101,596,0,0,1106,0,554,21201,1,0,-4,21102,1,1,-1,2207,-4,-2,10,1006,10,615,21101,0,0,-1,22202,-2,-1,-2,2107,0,-3,10,1006,10,637,22102,1,-1,1,21101,637,0,0,105,1,512,21202,-2,-1,-2,22201,-4,-2,-4,109,-5,2106,0,0
--- a/2019/day12/day12.rkt
+++ b/2019/day12/day12.rkt
@ -0,0 +1,64 @@
+#lang racket
+
+(struct moon
+  (x y z vx vy vz)
+  #:transparent)
+
+(define (read-input filename)
+  (with-input-from-file filename
+    (lambda ()
+      (for/list ([line (in-lines)])
+        (define positions-str
+          (cdr (regexp-match #rx"<x=(-?[0-9]+), y=(-?[0-9]+), z=(-?[0-9]+)>" line)))
+        (define positions (map string->number positions-str))
+        (apply moon (append positions '(0 0 0)))))))
+
+(define (step moons)
+  (for/list ([cur moons])
+    (define new-vx (moon-vx cur))
+    (define new-vy (moon-vy cur))
+    (define new-vz (moon-vz cur))
+    (define (gravity-pull pos-cur pos-other)
+      (cond
+        [(> pos-other pos-cur) 1]
+        [(< pos-other pos-cur) -1]
+        [else 0]))
+    (for ([other moons] #:unless (eq? other cur))
+      (set! new-vx (+ new-vx (gravity-pull (moon-x cur) (moon-x other))))
+      (set! new-vy (+ new-vy (gravity-pull (moon-y cur) (moon-y other))))
+      (set! new-vz (+ new-vz (gravity-pull (moon-z cur) (moon-z other)))))
+    (moon (+ (moon-x cur) new-vx)
+          (+ (moon-y cur) new-vy)
+          (+ (moon-z cur) new-vz)
+          new-vx
+          new-vy
+          new-vz)))
+
+(define (total-energy moons)
+  (for/sum ([m moons])
+    (* (+ (abs (moon-x m))
+          (abs (moon-y m))
+          (abs (moon-z m)))
+       (+ (abs (moon-vx m))
+          (abs (moon-vy m))
+          (abs (moon-vz m))))))
+
+(define (part1 filename)
+  (define moons (read-input filename))
+  (total-energy (for/fold ([ms moons]) ([i (in-range 1000)]) (step ms))))
+
+(define (cycle-length moons pos speed)
+  (define-values (states final)
+    (for/fold ([states (mutable-set)] [ms moons])
+              ([_ (in-naturals)]
+               #:break (set-member? states (append (map pos ms) (map speed ms))))
+      (set-add! states (append (map pos ms) (map speed ms)))
+      (values states (step ms))))
+  (set-count states))
+
+(define (part2 filename)
+  (define moons (read-input filename))
+  (define cycle-x (cycle-length moons moon-x moon-vx))
+  (define cycle-y (cycle-length moons moon-y moon-vy))
+  (define cycle-z (cycle-length moons moon-z moon-vz))
+  (lcm cycle-x cycle-y cycle-z))
--- a/2019/day12/input
+++ b/2019/day12/input
@ -0,0 +1,4 @@
+<x=-17, y=9, z=-5>
+<x=-1, y=7, z=13>
+<x=-19, y=12, z=5>
+<x=-6, y=-6, z=-4>
--- a/2019/day12/test
+++ b/2019/day12/test
@ -0,0 +1,4 @@
+<x=-1, y=0, z=2>
+<x=2, y=-10, z=-7>
+<x=4, y=-8, z=8>
+<x=3, y=5, z=-1>
--- a/2019/day12/test2
+++ b/2019/day12/test2
@ -0,0 +1,4 @@
+<x=-8, y=-10, z=0>
+<x=5, y=5, z=10>
+<x=2, y=-7, z=3>
+<x=9, y=-8, z=-3>
--- a/2019/day13/day13.rkt
+++ b/2019/day13/day13.rkt
@ -0,0 +1,74 @@
+#lang racket/base
+
+(require "../intcode.rkt"
+         racket/list)
+
+(module+ test
+  (require rackunit))
+
+(define (part1 program)
+  (define vm (execute (start-machine program '())))
+  (define screen
+    (let loop ([screen (hash)]
+               [instructions (reverse (machine-outputs vm))])
+      (if (empty? instructions)
+          screen
+          (let ([x (car instructions)]
+                [y (cadr instructions)]
+                [tile-id (caddr instructions)])
+            (loop (hash-set screen (list x y) tile-id)
+                  (cdddr instructions))))))
+  (for/sum ([(k v) (in-hash screen)]
+            #:when (= v 2))
+    1))
+
+(module+ test
+  (check-equal? (part1 (parse-file "input")) 363))
+
+(define (ball-x screen)
+  (for/first ([(k v) (in-hash screen)]
+              #:when (= v 4))
+    (car k)))
+
+(define (paddle-x screen)
+  (for/first ([(k v) (in-hash screen)]
+              #:when (= v 3))
+    (car k)))
+
+(define (block-count screen)
+  (for/sum ([(k v) (in-hash screen)]
+            #:when (= v 2))
+    1))
+
+(define (draw-screen screen instructions)
+  (if (empty? instructions)
+      screen
+      (let ([x (car instructions)]
+            [y (cadr instructions)]
+            [tile-id (caddr instructions)])
+        (draw-screen (hash-set screen (list x y) tile-id)
+                     (cdddr instructions)))))
+
+(define (part2 program)
+  (vector-set! program 0 2)
+  (define vm (execute (start-machine program '())))
+  (define screen
+    (let loop ([vm vm]
+               [screen (hash)])
+      (define new-screen (draw-screen screen (reverse (machine-outputs vm))))
+      (define ball-pos (ball-x new-screen))
+      (define paddle-pos (paddle-x new-screen))
+      (define joystick (cond
+                         [(< ball-pos paddle-pos) -1]
+                         [(= ball-pos paddle-pos) 0]
+                         [(> ball-pos paddle-pos) 1]))
+      (define new-vm
+        (execute (machine (machine-program vm) (list joystick)
+                          (machine-pc vm) (machine-relative-base vm) #f '())))
+      (if (= 0 (block-count new-screen))
+          new-screen
+          (loop new-vm new-screen))))
+  (hash-ref screen (list -1 0)))
+
+(module+ test
+  (check-equal? (part2 (parse-file "input")) 17159))
--- a/2019/day13/input
+++ b/2019/day13/input
--- a/2019/day14/day14.rkt
+++ b/2019/day14/day14.rkt
@ -0,0 +1,81 @@
+#lang racket
+
+(module+ test
+  (require rackunit))
+
+(module+ main
+  (displayln "Day 14"))
+
+(define (read-rules filename)
+  (with-input-from-file filename
+    (lambda ()
+      (define h (make-hash))
+      (for ([line (in-lines)])
+        (define rule
+          (for/list ([elt (regexp-match* #rx"([0-9]+) ([A-Z]+)" line #:match-select cdr)])
+            (list (string->number (car elt)) (string->symbol (cadr elt)))))
+        (define output (last rule))
+        (hash-set! h
+                   (cadr output)
+                   (cons (car output)
+                         (make-hash (for/list ([elt (drop-right rule 1)])
+                                      (cons (cadr elt) (car elt)))))))
+      h)))
+
+(define (generate! rules needed available)
+  (for ([(target target-amount) (in-hash needed)]
+        #:unless (eq? target 'ORE))
+    (define inputs (cdr (hash-ref rules target)))
+    (define output-amount (car (hash-ref rules target)))
+    (define new-target-amount (- target-amount (hash-ref available target 0)))
+    (define multiple (ceiling (/ new-target-amount output-amount)))
+    (hash-set! available target (- (* multiple output-amount) new-target-amount))
+    (hash-set! needed target 0)
+    (for ([(input input-amount) (in-hash inputs)])
+      (hash-update! needed input (lambda (v) (+ v (* multiple input-amount))) 0))))
+
+(define (ore-per-fuel rules amount)
+  (define needed (make-hash `((FUEL . ,amount))))
+  (define available (make-hash))
+  (for ([i (in-naturals)]
+        #:break (= (apply + (hash-values needed)) (hash-ref needed 'ORE 0)))
+    (generate! rules needed available))
+  (hash-ref needed 'ORE))
+
+(define (part1 filename)
+  (define rules (read-rules filename))
+  (ore-per-fuel rules 1))
+
+(module+ test
+  (check-eq? 31 (part1 "test1"))
+  (check-eq? 165 (part1 "test2"))
+  (check-eq? 13312 (part1 "test3"))
+  (check-eq? 180697 (part1 "test4"))
+  (check-eq? 2210736 (part1 "test5")))
+
+(module+ main
+  (display "Part 1: ")
+  (displayln (part1 "input")))
+
+(define (part2 filename)
+  (define rules (read-rules filename))
+  (define max-fuel 1000000000000)
+  (define min-fuel 1)
+  (bisect rules 1000000000000 min-fuel max-fuel))
+
+(define (bisect rules target-ore min-fuel max-fuel)
+  (define mid-fuel (floor (+ min-fuel (/ (- max-fuel min-fuel) 2))))
+  (define ore (ore-per-fuel rules mid-fuel))
+  (cond
+    [(= 1 (- max-fuel min-fuel)) min-fuel]
+    [(< ore target-ore) (bisect rules target-ore mid-fuel max-fuel)]
+    [(< target-ore ore) (bisect rules target-ore min-fuel mid-fuel)]))
+
+(module+ test
+  (check-eq? 82892753 (part2 "test3"))
+  (check-eq? 5586022 (part2 "test4"))
+  (check-eq? 460664 (part2 "test5")))
+
+(module+ main
+  (display "Part 2: ")
+  (displayln (part2 "input")))
--- a/2019/day14/input
+++ b/2019/day14/input
@ -0,0 +1,60 @@
+29 PQJGK => 4 SRPZP
+6 XKJP, 4 LDSMT => 6 ZVSMJ
+9 CGCPW, 2 CFVS => 7 DWZH
+1 VQWZC, 1 FRTJG => 1 MGLKL
+3 GCTBC, 4 RGKB => 4 RLZR
+2 LGLCP => 9 GCTBC
+3 DFPW, 12 FRTJG => 2 XVSRT
+1 VBXFG => 3 VQWZC
+1 GCTBC, 1 BVHM => 8 DGMZB
+7 DFPW, 3 JQNL => 7 FRTJG
+6 BHQN, 4 VXNP => 5 HBLQT
+1 XNBR, 27 FTBNQ, 2 RGKB => 7 JZPMK
+6 HKMV, 4 JHDHS, 11 NMSKF => 9 STCX
+129 ORE => 5 NVXTP
+13 BVHM, 5 XNBR => 3 LKXML
+3 SBPM, 4 LDSMT, 13 GPBG => 6 HXFCJ
+1 XVSRT, 1 JHDHS => 4 FTBNQ
+6 LKXML, 6 HRLWP => 5 PSJK
+5 HRLWP, 19 PDHVG => 1 VRQD
+3 FTBNQ, 1 QLKTZ => 7 SBPM
+2 VXNP => 3 XKJP
+4 SRPZP, 7 XVSRT => 8 LMVF
+2 GPBG, 8 DWZH, 3 JTCHR, 10 RLZR, 1 CFVS, 20 BFCZ => 2 WZSTV
+130 ORE => 9 JQNL
+100 ORE => 4 VBXFG
+4 XNBR => 8 RDSHN
+2 CDBTL, 2 XNBR, 8 QLKTZ => 6 CGCPW
+7 CGCPW => 6 BFCZ
+7 FTBNQ, 7 VXNP => 1 BVHM
+1 HXFCJ, 15 CSXD => 1 DFXPB
+1 MCRW, 6 MGLKL, 1 HBLQT => 8 SWRV
+19 BZQGL, 10 NMSKF, 20 WZSTV, 15 LVGB, 26 FTBNQ, 45 DWZH, 2 FJWVP, 56 JZPMK => 1 FUEL
+12 JTCHR => 4 CDBTL
+1 MGLKL => 6 PQJGK
+1 NVXTP => 1 LDSMT
+3 SWRV, 1 LGLCP => 2 GHVJ
+4 DGMZB, 11 HXFCJ, 2 RLZR => 4 SHTB
+5 GHVJ, 1 RGKB, 1 GCTBC => 6 HKMV
+1 SRPZP => 9 XNBR
+1 ZVSMJ => 2 JHDHS
+9 SWRV => 5 NMSKF
+1 NVXTP => 3 XKBS
+7 BHQN => 2 GPBG
+21 NMSKF, 12 FTBNQ, 12 SBPM => 3 CMXK
+2 GPBG, 12 ZVSMJ, 2 PDHVG => 4 LGLCP
+158 ORE => 8 DFPW
+3 BVHM, 1 HXFCJ, 5 CGCPW, 5 BFCZ, 6 VRQD, 3 LDSMT => 7 LVGB
+1 XVSRT, 1 XKJP => 8 PDHVG
+3 VRQD, 16 SHTB, 5 SBPM => 9 BZQGL
+1 BVHM, 3 HKMV => 4 CFVS
+13 JQNL => 7 VXNP
+1 XKJP, 6 XVSRT => 7 MCRW
+15 NVXTP, 19 XKBS => 4 BHQN
+8 JHDHS, 5 CMXK, 2 GPBG => 8 CSXD
+1 JZBR, 13 LKXML, 1 HKMV, 9 DFXPB, 3 XKBS, 2 PSJK, 2 LMVF, 15 HRLWP => 7 FJWVP
+1 CGCPW, 3 RDSHN => 8 JZBR
+24 PQJGK => 5 JTCHR
+1 XVSRT, 5 LDSMT => 6 QLKTZ
+17 GPBG => 7 RGKB
+4 STCX => 1 HRLWP
--- a/2019/day14/test1
+++ b/2019/day14/test1
@ -0,0 +1,6 @@
+10 ORE => 10 A
+1 ORE => 1 B
+7 A, 1 B => 1 C
+7 A, 1 C => 1 D
+7 A, 1 D => 1 E
+7 A, 1 E => 1 FUEL
--- a/2019/day14/test2
+++ b/2019/day14/test2
@ -0,0 +1,7 @@
+9 ORE => 2 A
+8 ORE => 3 B
+7 ORE => 5 C
+3 A, 4 B => 1 AB
+5 B, 7 C => 1 BC
+4 C, 1 A => 1 CA
+2 AB, 3 BC, 4 CA => 1 FUEL
--- a/2019/day14/test3
+++ b/2019/day14/test3
@ -0,0 +1,9 @@
+157 ORE => 5 NZVS
+165 ORE => 6 DCFZ
+44 XJWVT, 5 KHKGT, 1 QDVJ, 29 NZVS, 9 GPVTF, 48 HKGWZ => 1 FUEL
+12 HKGWZ, 1 GPVTF, 8 PSHF => 9 QDVJ
+179 ORE => 7 PSHF
+177 ORE => 5 HKGWZ
+7 DCFZ, 7 PSHF => 2 XJWVT
+165 ORE => 2 GPVTF
+3 DCFZ, 7 NZVS, 5 HKGWZ, 10 PSHF => 8 KHKGT
--- a/2019/day14/test4
+++ b/2019/day14/test4
@ -0,0 +1,12 @@
+2 VPVL, 7 FWMGM, 2 CXFTF, 11 MNCFX => 1 STKFG
+17 NVRVD, 3 JNWZP => 8 VPVL
+53 STKFG, 6 MNCFX, 46 VJHF, 81 HVMC, 68 CXFTF, 25 GNMV => 1 FUEL
+22 VJHF, 37 MNCFX => 5 FWMGM
+139 ORE => 4 NVRVD
+144 ORE => 7 JNWZP
+5 MNCFX, 7 RFSQX, 2 FWMGM, 2 VPVL, 19 CXFTF => 3 HVMC
+5 VJHF, 7 MNCFX, 9 VPVL, 37 CXFTF => 6 GNMV
+145 ORE => 6 MNCFX
+1 NVRVD => 8 CXFTF
+1 VJHF, 6 MNCFX => 4 RFSQX
+176 ORE => 6 VJHF
--- a/2019/day14/test5
+++ b/2019/day14/test5
@ -0,0 +1,17 @@
+171 ORE => 8 CNZTR
+7 ZLQW, 3 BMBT, 9 XCVML, 26 XMNCP, 1 WPTQ, 2 MZWV, 1 RJRHP => 4 PLWSL
+114 ORE => 4 BHXH
+14 VRPVC => 6 BMBT
+6 BHXH, 18 KTJDG, 12 WPTQ, 7 PLWSL, 31 FHTLT, 37 ZDVW => 1 FUEL
+6 WPTQ, 2 BMBT, 8 ZLQW, 18 KTJDG, 1 XMNCP, 6 MZWV, 1 RJRHP => 6 FHTLT
+15 XDBXC, 2 LTCX, 1 VRPVC => 6 ZLQW
+13 WPTQ, 10 LTCX, 3 RJRHP, 14 XMNCP, 2 MZWV, 1 ZLQW => 1 ZDVW
+5 BMBT => 4 WPTQ
+189 ORE => 9 KTJDG
+1 MZWV, 17 XDBXC, 3 XCVML => 2 XMNCP
+12 VRPVC, 27 CNZTR => 2 XDBXC
+15 KTJDG, 12 BHXH => 5 XCVML
+3 BHXH, 2 VRPVC => 7 MZWV
+121 ORE => 7 VRPVC
+7 XCVML => 6 RJRHP
+5 BHXH, 4 VRPVC => 5 LTCX
--- a/2019/day15/day15.rkt
+++ b/2019/day15/day15.rkt
@ -0,0 +1,64 @@
+#lang racket/base
+
+(require racket/random
+         racket/list
+         racket/match
+         graph
+         "../intcode.rkt")
+
+(module+ test
+  (require rackunit))
+
+(define (possible-directions grid pos)
+  (define unexplored-directions
+    (for/list ([step '(-1 -i 1 +i)]
+               #:unless (hash-has-key? grid (+ pos step)))
+      step))
+  (if (empty? unexplored-directions)
+      (for/list ([step '(-1 -i 1 +i)]
+                 #:unless (eq? 'wall (hash-ref grid (+ pos step) 'floor)))
+        step)
+      unexplored-directions))
+
+(define (shortest-distances grid source)
+  (define g (unweighted-graph/undirected
+             (for*/list ([(pos tile) (in-hash grid)]
+                         #:unless (eq? 'wall tile)
+                         [step '(-1 -i 1 +i)]
+                         #:unless (eq? 'wall (hash-ref grid (+ pos step) 'wall)))
+               (list pos (+ pos step)))))
+  (define-values (distances predecessors) (dijkstra g source))
+  distances)
+
+(define (part12 program)
+  (define grid (make-hash '((0 'floor))))
+  (let loop ([vm (execute (start-machine program '()))]
+             [pos 0]
+             [i 0])
+    (define direction (random-ref (possible-directions grid pos)))
+    (define direction-code (match direction
+                             [+i 1]
+                             [-i 2]
+                             [-1 3]
+                             [1 4]))
+    (define new-vm (execute (struct-copy machine vm [inputs (list direction-code)])))
+    (define next-pos (+ pos direction))
+    (unless (> i 100000)
+      (match (car (machine-outputs new-vm))
+        [0 (hash-set! grid next-pos 'wall)
+           (loop new-vm pos (add1 i))]
+        [1 (hash-set! grid next-pos 'floor)
+           (loop new-vm next-pos (add1 i))]
+        [2 (hash-set! grid next-pos 'oxygen)
+           (loop new-vm next-pos (add1 i))])))
+  (define oxygen (for/first ([(pos tile) (in-hash grid)]
+                             #:when (eq? 'oxygen tile))
+                   pos))
+  (define distances (shortest-distances grid oxygen))
+  (values (hash-ref distances 0)
+          (apply max (hash-values distances))))
+
+(module+ test
+  (define-values (p1 p2) (part12 (parse-file "input")))
+  (check-equal? p1 296)
+  (check-equal? p2 302))
--- a/2019/day15/input
+++ b/2019/day15/input
@ -0,0 +1 @@
+3,1033,1008,1033,1,1032,1005,1032,31,1008,1033,2,1032,1005,1032,58,1008,1033,3,1032,1005,1032,81,1008,1033,4,1032,1005,1032,104,99,102,1,1034,1039,1001,1036,0,1041,1001,1035,-1,1040,1008,1038,0,1043,102,-1,1043,1032,1,1037,1032,1042,1105,1,124,102,1,1034,1039,102,1,1036,1041,1001,1035,1,1040,1008,1038,0,1043,1,1037,1038,1042,1105,1,124,1001,1034,-1,1039,1008,1036,0,1041,101,0,1035,1040,1002,1038,1,1043,1001,1037,0,1042,1105,1,124,1001,1034,1,1039,1008,1036,0,1041,102,1,1035,1040,1002,1038,1,1043,102,1,1037,1042,1006,1039,217,1006,1040,217,1008,1039,40,1032,1005,1032,217,1008,1040,40,1032,1005,1032,217,1008,1039,5,1032,1006,1032,165,1008,1040,1,1032,1006,1032,165,1101,0,2,1044,1105,1,224,2,1041,1043,1032,1006,1032,179,1102,1,1,1044,1105,1,224,1,1041,1043,1032,1006,1032,217,1,1042,1043,1032,1001,1032,-1,1032,1002,1032,39,1032,1,1032,1039,1032,101,-1,1032,1032,101,252,1032,211,1007,0,56,1044,1105,1,224,1102,0,1,1044,1106,0,224,1006,1044,247,102,1,1039,1034,1001,1040,0,1035,101,0,1041,1036,102,1,1043,1038,102,1,1042,1037,4,1044,1106,0,0,40,31,67,22,98,81,11,5,82,25,86,22,69,15,21,97,6,6,62,50,91,14,90,37,26,50,98,4,55,61,39,20,93,19,70,47,50,8,85,97,24,91,12,79,38,62,13,99,4,63,48,75,93,2,4,62,72,51,63,23,12,8,80,87,54,13,99,85,2,66,45,93,13,2,87,86,14,25,27,12,87,49,58,51,77,25,5,97,13,35,48,64,63,11,76,32,18,79,37,88,12,85,85,4,69,71,29,27,66,33,7,66,72,51,74,87,13,48,42,34,67,26,13,96,25,65,83,46,72,99,25,62,3,50,72,99,65,37,75,39,68,39,11,75,27,70,90,39,62,69,31,17,57,43,27,28,54,87,7,97,72,25,93,30,59,20,74,59,7,8,94,96,36,86,9,35,81,74,21,73,15,59,6,80,42,5,67,34,55,95,96,31,98,70,50,17,64,36,79,34,31,20,58,60,9,4,55,39,94,49,17,95,81,85,31,26,62,80,4,71,80,17,37,80,97,9,16,25,89,6,46,76,50,99,20,62,73,6,79,66,96,2,42,72,45,96,30,94,73,42,38,63,12,36,68,70,50,54,26,74,49,92,26,33,38,66,65,79,90,55,37,71,48,66,5,57,86,17,42,89,5,97,81,46,99,74,19,69,13,86,60,93,7,16,86,42,81,26,95,91,93,14,94,76,91,33,44,42,58,87,26,41,9,22,63,1,82,63,20,49,50,71,75,5,32,73,14,45,98,50,91,54,69,61,27,60,40,88,16,34,18,64,18,50,81,67,67,28,95,7,89,80,37,26,97,25,29,58,77,60,22,22,43,64,15,66,69,33,20,50,84,70,53,11,64,80,16,80,74,15,90,67,33,12,57,8,52,78,10,18,25,40,82,63,93,93,28,18,51,68,58,6,60,58,14,54,72,68,91,41,70,67,3,74,18,3,27,65,71,11,11,99,49,88,21,42,7,78,35,4,78,2,2,82,26,65,97,67,46,63,1,68,55,85,94,16,1,22,41,67,86,35,10,83,64,11,95,50,46,86,74,5,68,81,62,22,75,68,26,58,40,62,44,38,65,22,69,20,90,5,10,42,99,96,51,63,64,7,64,36,92,89,54,4,68,63,85,9,38,95,89,51,50,75,86,5,41,40,59,31,82,99,8,95,5,43,45,60,60,29,84,15,5,96,64,55,97,44,35,7,93,96,43,22,50,20,70,81,39,8,90,50,66,49,31,29,34,97,90,1,59,3,5,82,85,85,47,29,6,65,31,70,76,33,35,82,43,98,62,29,44,76,70,59,89,30,25,97,83,75,79,43,98,93,40,59,36,55,64,29,31,98,65,47,33,91,75,62,71,68,38,33,81,10,73,83,6,13,88,92,45,94,15,1,88,59,22,7,36,89,59,36,12,80,3,80,78,29,85,75,28,7,15,82,41,1,81,26,7,72,46,85,71,16,40,73,11,81,7,24,10,87,75,9,87,35,40,86,5,16,69,98,45,43,8,68,20,83,73,47,86,77,35,89,71,1,37,62,62,65,44,26,83,52,87,89,40,62,61,97,7,42,79,9,1,64,99,86,5,86,51,23,25,32,71,28,91,26,87,64,47,17,2,90,64,42,10,85,36,31,79,75,79,21,59,5,9,88,12,36,74,59,72,6,82,34,80,10,78,81,33,91,22,94,18,88,10,63,23,87,58,65,20,66,74,65,18,96,22,98,13,86,48,67,14,96,58,73,14,67,2,65,48,92,42,93,18,96,32,81,0,0,21,21,1,10,1,0,0,0,0,0,0
--- a/2019/day16/day16.rkt
+++ b/2019/day16/day16.rkt
@ -0,0 +1,73 @@
+#lang racket
+
+(require racket/sequence)
+
+(module+ test
+  (require rackunit))
+
+(define (pattern n i)
+  (define index (remainder (add1 i) (* 4 n)))
+  (cond
+    [(< index n) 0]
+    [(< index (* 2 n)) 1]
+    [(< index (* 3 n)) 0]
+    [(< index (* 4 n)) -1]))
+
+(define (last-digit n)
+  (abs (remainder n 10)))
+
+(define (phase signal)
+  (for/list ([i (in-range (length signal))])
+    (last-digit (for/sum ([d (in-list signal)]
+                          [j (in-naturals)]
+                          #:when (>= j i))
+                  (* d (pattern (add1 i) j))))))
+
+(define (number->digits n)
+  (define (aux n)
+    (define-values (q r) (quotient/remainder n 10))
+    (if (> q 0)
+        (cons r (aux q))
+        (list r)))
+  (reverse (aux n)))
+
+(define (digits->number lst)
+  (for/sum ([d (in-list (reverse lst))]
+            [i (in-naturals)])
+    (* d (expt 10 i))))
+
+(define (apply-n-times f n x)
+  (for/fold ([val x]) ([i (in-range n)])
+    (f val)))
+
+(define (part1 n)
+  (digits->number (take (apply-n-times phase 100 n) 8)))
+
+(module+ test
+  (check-eq? (part1 (number->digits 80871224585914546619083218645595)) 24176176)
+  (check-eq? (part1 (number->digits 19617804207202209144916044189917)) 73745418)
+  (check-eq? (part1 (number->digits 69317163492948606335995924319873)) 52432133))
+
+(module+ main
+  (define input (number->digits
+                 (string->number
+                  (string-trim
+                   (port->string (open-input-file "input") #:close? #t)))))
+  (displayln (part1 input)))
+
+(define (phase2 signal)
+  (define-values (s res)
+    (for/fold ([s (apply + signal)]
+               [res '()])
+              ([d (in-list signal)])
+      (values (- s d) (cons (last-digit s) res))))
+  (reverse res))
+
+(define (part2 input)
+  (define offset (digits->number (take input 7)))
+  (define n (drop input offset))
+  (digits->number (take (apply-n-times phase2 100 n) 8)))
+
+(module+ main
+  (define input2 (flatten (make-list 10000 input)))
+  (displayln (part2 input2)))
--- a/2019/day16/input
+++ b/2019/day16/input
@ -0,0 +1 @@
+59749012692497360857047467554796667139266971954850723493205431123165826080869880148759586023048633544809012786925668551639957826693687972765764376332866751104713940802555266397289142675218037547096634248307260671899871548313611756525442595930474639845266351381011380170903695947253040751698337167594183713030695951696818950161554630424143678657203441568388368475123279525515262317457621810448095399401556723919452322199989580496608898965260381604485810760050252737127446449982328185199195622241930968611065497781555948187157418339240689789877555108205275435831320988202725926797165070246910002881692028525921087207954194585166525017611171911807360959
--- a/2019/day17/day17.rkt
+++ b/2019/day17/day17.rkt
@ -0,0 +1,105 @@
+#lang racket/base
+
+(require "../intcode.rkt"
+         racket/match
+         racket/set
+         racket/list
+         racket/string)
+
+(module+ test
+  (require rackunit))
+
+(define (get-grid program)
+  (define vm (execute (start-machine program '())))
+  (define map-str (list->ascii (reverse (machine-outputs vm))))
+  (define-values (grid robot-pos robot-dir pos)
+    (for/fold ([grid (set)]
+               [robot-pos #f]
+               [robot-dir #f]
+               [pos 0])
+              ([c (in-list (reverse (machine-outputs vm)))])
+      (match (integer->char c)
+        [#\newline (values grid robot-pos robot-dir (make-rectangular 0 (add1 (imag-part pos))))]
+        [#\# (values (set-add grid pos) robot-pos robot-dir (add1 pos))]
+        [#\^ (values grid pos -i (add1 pos))]
+        [#\v (values grid pos +i (add1 pos))]
+        [#\< (values grid pos -1 (add1 pos))]
+        [#\> (values grid pos 1 (add1 pos))]
+        [x (values grid robot-pos robot-dir (add1 pos))])))
+  (values map-str grid robot-pos robot-dir))
+
+(define (part1 program)
+  (define-values (map-str grid robot-pos robot-dir) (get-grid program))
+  (define intersections
+    (for/list ([x (in-set grid)]
+               #:when (for/and ([step '(-i -1 +i 1)])
+                        (set-member? grid (+ x step))))
+      x))
+  (for/sum ([int (in-list intersections)])
+    (* (real-part int) (imag-part int))))
+
+(module+ test
+  (check-equal? (part1 (parse-file "input")) 5972))
+
+(define (find-direction grid robot-pos robot-dir)
+  (for/first ([step '(-i +i -1 1)]
+              #:unless (= step (- robot-dir))
+              #:when (set-member? grid (+ robot-pos step)))
+    step))
+
+(define (get-path grid robot-pos robot-dir)
+  (define path
+    (let loop ([pos robot-pos]
+               [dir robot-dir]
+               [len 0]
+               [path '()])
+      (if (set-member? grid (+ pos dir))
+          (loop (+ pos dir) dir (add1 len) path)
+          (let ([new-dir (find-direction grid pos dir)]
+                [new-path (cons len path)])
+            (if new-dir
+                (loop pos new-dir 0 (cons (match (/ new-dir dir) [+i 'R] [-i 'L]) new-path))
+                (cdr (reverse new-path)))))))
+  path)
+
+(define (remove-substring lst sublst)
+  (cond
+    [(empty? lst) '()]
+    [(list-prefix? sublst lst) (remove-substring (drop lst (length sublst)) sublst)]
+    [else (cons (car lst) (remove-substring (cdr lst) sublst))]))
+
+(define (compress path)
+  (define (prefixes lst)
+    (for/list ([size (in-range 2 10 2)])
+      (take lst size)))
+  (define possibilities
+    (for*/list ([a (in-list (prefixes path))]
+                [b (in-list (prefixes (remove-substring path a)))]
+                [c (in-list (prefixes (remove-substring (remove-substring path a) b)))]
+                #:when (empty? (remove-substring (remove-substring (remove-substring path a) b) c)))
+      (list a b c)))
+  (for/last ([poss (in-list possibilities)])
+    (match-define (list a b c) poss)
+    (define result (let loop ([lst path])
+                     (cond
+                       [(empty? lst) '()]
+                       [(list-prefix? c lst) (cons 'C (loop (drop lst (length c))))]
+                       [(list-prefix? b lst) (cons 'B (loop (drop lst (length b))))]
+                       [(list-prefix? a lst) (cons 'A (loop (drop lst (length a))))]
+                       [else '(#f)])))
+    #:final (last result)
+    (list result a b c)))
+
+(define (lst->str path)
+  (string-join (map (λ (v) (format "~a" v)) path) ","))
+
+(define (part2 program)
+  (define-values (map-str grid robot-pos robot-dir) (get-grid program))
+  (define path (get-path grid robot-pos robot-dir))
+  (define inputs (string-join (append (map lst->str (compress path)) '("n\n")) "\n"))
+  (vector-set! program 0 2)
+  (define vm (execute (start-machine program inputs)))
+  (car (machine-outputs vm)))
+
+(module+ test
+  (check-equal? (part2 (parse-file "input")) 933214))
--- a/2019/day17/input
+++ b/2019/day17/input
@ -0,0 +1 @@
+1,330,331,332,109,3546,1101,0,1182,15,1101,1481,0,24,1001,0,0,570,1006,570,36,102,1,571,0,1001,570,-1,570,1001,24,1,24,1105,1,18,1008,571,0,571,1001,15,1,15,1008,15,1481,570,1006,570,14,21102,58,1,0,1106,0,786,1006,332,62,99,21101,0,333,1,21101,0,73,0,1106,0,579,1101,0,0,572,1101,0,0,573,3,574,101,1,573,573,1007,574,65,570,1005,570,151,107,67,574,570,1005,570,151,1001,574,-64,574,1002,574,-1,574,1001,572,1,572,1007,572,11,570,1006,570,165,101,1182,572,127,1002,574,1,0,3,574,101,1,573,573,1008,574,10,570,1005,570,189,1008,574,44,570,1006,570,158,1105,1,81,21102,1,340,1,1106,0,177,21102,1,477,1,1106,0,177,21101,0,514,1,21102,1,176,0,1105,1,579,99,21102,1,184,0,1106,0,579,4,574,104,10,99,1007,573,22,570,1006,570,165,102,1,572,1182,21102,375,1,1,21101,211,0,0,1106,0,579,21101,1182,11,1,21101,0,222,0,1106,0,979,21102,388,1,1,21102,1,233,0,1106,0,579,21101,1182,22,1,21102,1,244,0,1106,0,979,21101,0,401,1,21102,255,1,0,1106,0,579,21101,1182,33,1,21102,266,1,0,1105,1,979,21102,414,1,1,21102,1,277,0,1105,1,579,3,575,1008,575,89,570,1008,575,121,575,1,575,570,575,3,574,1008,574,10,570,1006,570,291,104,10,21102,1,1182,1,21102,1,313,0,1105,1,622,1005,575,327,1102,1,1,575,21101,0,327,0,1106,0,786,4,438,99,0,1,1,6,77,97,105,110,58,10,33,10,69,120,112,101,99,116,101,100,32,102,117,110,99,116,105,111,110,32,110,97,109,101,32,98,117,116,32,103,111,116,58,32,0,12,70,117,110,99,116,105,111,110,32,65,58,10,12,70,117,110,99,116,105,111,110,32,66,58,10,12,70,117,110,99,116,105,111,110,32,67,58,10,23,67,111,110,116,105,110,117,111,117,115,32,118,105,100,101,111,32,102,101,101,100,63,10,0,37,10,69,120,112,101,99,116,101,100,32,82,44,32,76,44,32,111,114,32,100,105,115,116,97,110,99,101,32,98,117,116,32,103,111,116,58,32,36,10,69,120,112,101,99,116,101,100,32,99,111,109,109,97,32,111,114,32,110,101,119,108,105,110,101,32,98,117,116,32,103,111,116,58,32,43,10,68,101,102,105,110,105,116,105,111,110,115,32,109,97,121,32,98,101,32,97,116,32,109,111,115,116,32,50,48,32,99,104,97,114,97,99,116,101,114,115,33,10,94,62,118,60,0,1,0,-1,-1,0,1,0,0,0,0,0,0,1,12,18,0,109,4,2102,1,-3,587,20101,0,0,-1,22101,1,-3,-3,21101,0,0,-2,2208,-2,-1,570,1005,570,617,2201,-3,-2,609,4,0,21201,-2,1,-2,1106,0,597,109,-4,2106,0,0,109,5,2102,1,-4,630,20102,1,0,-2,22101,1,-4,-4,21101,0,0,-3,2208,-3,-2,570,1005,570,781,2201,-4,-3,653,20102,1,0,-1,1208,-1,-4,570,1005,570,709,1208,-1,-5,570,1005,570,734,1207,-1,0,570,1005,570,759,1206,-1,774,1001,578,562,684,1,0,576,576,1001,578,566,692,1,0,577,577,21101,0,702,0,1105,1,786,21201,-1,-1,-1,1106,0,676,1001,578,1,578,1008,578,4,570,1006,570,724,1001,578,-4,578,21102,731,1,0,1105,1,786,1106,0,774,1001,578,-1,578,1008,578,-1,570,1006,570,749,1001,578,4,578,21102,1,756,0,1105,1,786,1105,1,774,21202,-1,-11,1,22101,1182,1,1,21101,0,774,0,1106,0,622,21201,-3,1,-3,1106,0,640,109,-5,2106,0,0,109,7,1005,575,802,21001,576,0,-6,20102,1,577,-5,1106,0,814,21102,1,0,-1,21102,0,1,-5,21102,0,1,-6,20208,-6,576,-2,208,-5,577,570,22002,570,-2,-2,21202,-5,59,-3,22201,-6,-3,-3,22101,1481,-3,-3,2101,0,-3,843,1005,0,863,21202,-2,42,-4,22101,46,-4,-4,1206,-2,924,21102,1,1,-1,1105,1,924,1205,-2,873,21102,35,1,-4,1105,1,924,2101,0,-3,878,1008,0,1,570,1006,570,916,1001,374,1,374,1202,-3,1,895,1101,0,2,0,2101,0,-3,902,1001,438,0,438,2202,-6,-5,570,1,570,374,570,1,570,438,438,1001,578,558,921,21002,0,1,-4,1006,575,959,204,-4,22101,1,-6,-6,1208,-6,59,570,1006,570,814,104,10,22101,1,-5,-5,1208,-5,35,570,1006,570,810,104,10,1206,-1,974,99,1206,-1,974,1101,0,1,575,21102,973,1,0,1105,1,786,99,109,-7,2105,1,0,109,6,21101,0,0,-4,21102,0,1,-3,203,-2,22101,1,-3,-3,21208,-2,82,-1,1205,-1,1030,21208,-2,76,-1,1205,-1,1037,21207,-2,48,-1,1205,-1,1124,22107,57,-2,-1,1205,-1,1124,21201,-2,-48,-2,1106,0,1041,21102,1,-4,-2,1106,0,1041,21101,0,-5,-2,21201,-4,1,-4,21207,-4,11,-1,1206,-1,1138,2201,-5,-4,1059,1202,-2,1,0,203,-2,22101,1,-3,-3,21207,-2,48,-1,1205,-1,1107,22107,57,-2,-1,1205,-1,1107,21201,-2,-48,-2,2201,-5,-4,1090,20102,10,0,-1,22201,-2,-1,-2,2201,-5,-4,1103,1202,-2,1,0,1105,1,1060,21208,-2,10,-1,1205,-1,1162,21208,-2,44,-1,1206,-1,1131,1105,1,989,21101,0,439,1,1106,0,1150,21102,477,1,1,1106,0,1150,21101,0,514,1,21102,1,1149,0,1105,1,579,99,21101,0,1157,0,1106,0,579,204,-2,104,10,99,21207,-3,22,-1,1206,-1,1138,2101,0,-5,1176,1201,-4,0,0,109,-6,2105,1,0,6,13,27,13,6,1,11,1,27,1,11,1,6,1,11,1,27,1,11,1,6,1,11,1,27,1,11,1,6,1,11,1,27,1,11,1,6,1,11,1,27,1,11,1,6,1,11,1,1,9,9,11,9,1,6,1,11,1,1,1,7,1,9,1,7,1,1,1,9,1,6,1,11,13,7,1,7,1,1,1,9,1,6,1,13,1,7,1,1,1,7,1,7,1,1,1,9,1,6,1,13,1,7,1,1,1,5,11,1,1,9,1,6,1,13,1,7,1,1,1,5,1,1,1,9,1,9,1,6,11,3,1,7,1,1,1,5,1,1,1,9,1,1,9,16,1,3,1,7,1,1,1,5,1,1,1,9,1,1,1,24,1,3,1,7,13,7,1,1,1,24,1,3,1,9,1,5,1,1,1,1,1,7,1,1,1,24,1,3,1,9,9,1,1,7,11,16,1,3,1,15,1,3,1,9,1,7,1,12,9,15,1,3,1,9,1,7,1,16,1,19,1,3,1,9,1,7,1,16,1,19,11,3,1,7,1,16,1,23,1,5,1,3,1,7,1,8,9,23,11,7,1,8,1,37,1,11,1,8,1,37,1,11,1,8,1,37,1,11,1,8,1,37,1,11,1,8,1,37,1,11,1,8,1,37,13,8,1,58,1,58,1,58,1,58,1,50,9,50
--- a/2019/day19/day19.rkt
+++ b/2019/day19/day19.rkt
@ -0,0 +1,29 @@
+#lang racket/base
+
+(require "../intcode.rkt")
+
+(module+ test
+  (require rackunit))
+
+(define (pulled? program x y)
+  (define vm (execute (start-machine program (list x y))))
+  (= 1 (car (machine-outputs vm))))
+
+(define (part1 program)
+  (length (for*/list ([x (in-range 50)]
+                      [y (in-range 50)]
+                      #:when (pulled? program x y))
+            (list x y))))
+
+(module+ test
+  (check-equal? (part1 (parse-file "input")) 229))
+
+(define (part2 program)
+  (let loop ([x 0] [y 99])
+    (cond
+      [(not (pulled? program x y)) (loop (add1 x) y)]
+      [(pulled? program (+ x 99) (- y 99)) (+ (* 10000 x) (- y 99))]
+      [else (loop x (add1 y))])))
+
+(module+ test
+  (check-equal? (part2 (parse-file "input")) 6950903))
--- a/2019/day19/input
+++ b/2019/day19/input
@ -0,0 +1 @@
+109,424,203,1,21101,11,0,0,1105,1,282,21102,1,18,0,1106,0,259,1201,1,0,221,203,1,21101,0,31,0,1106,0,282,21101,0,38,0,1105,1,259,21002,23,1,2,21201,1,0,3,21101,0,1,1,21101,0,57,0,1106,0,303,2102,1,1,222,21002,221,1,3,20102,1,221,2,21102,259,1,1,21101,0,80,0,1105,1,225,21102,1,118,2,21102,91,1,0,1105,1,303,2102,1,1,223,21001,222,0,4,21102,259,1,3,21101,0,225,2,21101,225,0,1,21101,0,118,0,1105,1,225,20101,0,222,3,21102,1,72,2,21102,133,1,0,1106,0,303,21202,1,-1,1,22001,223,1,1,21102,1,148,0,1105,1,259,1201,1,0,223,20101,0,221,4,20101,0,222,3,21101,22,0,2,1001,132,-2,224,1002,224,2,224,1001,224,3,224,1002,132,-1,132,1,224,132,224,21001,224,1,1,21102,1,195,0,106,0,108,20207,1,223,2,20101,0,23,1,21102,-1,1,3,21102,214,1,0,1105,1,303,22101,1,1,1,204,1,99,0,0,0,0,109,5,1201,-4,0,249,22101,0,-3,1,22101,0,-2,2,22101,0,-1,3,21101,0,250,0,1105,1,225,21202,1,1,-4,109,-5,2105,1,0,109,3,22107,0,-2,-1,21202,-1,2,-1,21201,-1,-1,-1,22202,-1,-2,-2,109,-3,2106,0,0,109,3,21207,-2,0,-1,1206,-1,294,104,0,99,22102,1,-2,-2,109,-3,2105,1,0,109,5,22207,-3,-4,-1,1206,-1,346,22201,-4,-3,-4,21202,-3,-1,-1,22201,-4,-1,2,21202,2,-1,-1,22201,-4,-1,1,22101,0,-2,3,21101,0,343,0,1106,0,303,1105,1,415,22207,-2,-3,-1,1206,-1,387,22201,-3,-2,-3,21202,-2,-1,-1,22201,-3,-1,3,21202,3,-1,-1,22201,-3,-1,2,21202,-4,1,1,21101,384,0,0,1106,0,303,1106,0,415,21202,-4,-1,-4,22201,-4,-3,-4,22202,-3,-2,-2,22202,-2,-4,-4,22202,-3,-2,-3,21202,-4,-1,-2,22201,-3,-2,1,21201,1,0,-4,109,-5,2106,0,0
--- a/2019/day21/day21.rkt
+++ b/2019/day21/day21.rkt
@ -0,0 +1,43 @@
+#lang racket/base
+
+(require "../intcode.rkt")
+
+(module+ test
+  (require rackunit))
+
+(define (part1 program)
+  (define inputs #<<EOF
+OR A J
+AND B J
+AND C J
+NOT J J
+AND D J
+WALK
+
+EOF
+    )
+  (define vm (execute (start-machine program inputs)))
+  (car (machine-outputs vm)))
+
+(module+ test
+  (check-equal? (part1 (parse-file "input")) 19359533))
+
+(define (part2 program)
+  (define inputs #<<EOF
+OR A J
+AND B J
+AND C J
+NOT J J
+AND D J
+OR E T
+OR H T
+AND T J
+RUN
+
+EOF
+    )
+  (define vm (execute (start-machine program inputs)))
+  (car (machine-outputs vm)))
+
+(module+ test
+  (check-equal? (part2 (parse-file "input")) 1140310551))
--- a/2019/day21/input
+++ b/2019/day21/input
--- a/2019/day22/day22.rkt
+++ b/2019/day22/day22.rkt
@ -0,0 +1,117 @@
+#lang racket
+
+(require racket/string
+         math/number-theory)
+
+(module+ test
+  (require rackunit))
+
+(module+ main
+  (displayln "Day 22"))
+
+(define (read-instructions filename)
+  (with-input-from-file filename
+    (lambda ()
+      (for/list ([line (in-lines)])
+        (cond
+          [(string-prefix? line "deal into new stack") 'deal]
+          [(string-prefix? line "cut") `(cut ,(string->number (last (string-split line " "))))]
+          [(string-prefix? line "deal with increment") `(increment ,(string->number (last (string-split line " "))))]
+          [else 'other])))))
+
+(define (deal deck)
+  (reverse deck))
+
+(define (cut deck n)
+  (define split-fn (if (> n 0) split-at split-at-right))
+  (define-values (a b) (split-fn deck (abs n)))
+  (append b a))
+
+(define (increment deck n)
+  (for/list ([i (in-range (length deck))])
+    (list-ref deck
+              (remainder (* i (modular-inverse n (length deck))) (length deck)))))
+
+(define (execute instruction deck)
+  (match instruction
+    ['deal (deal deck)]
+    [(list 'cut n) (cut deck n)]
+    [(list 'increment n) (increment deck n)]))
+
+(define (shuffle deck instructions)
+  (for/fold ([d deck]) ([i instructions])
+    (execute i d)))
+
+(module+ test
+  (check-equal? (shuffle (range 10) (read-instructions "test1")) '(0 3 6 9 2 5 8 1 4 7))
+  (check-equal? (shuffle (range 10) (read-instructions "test2")) '(3 0 7 4 1 8 5 2 9 6))
+  (check-equal? (shuffle (range 10) (read-instructions "test3")) '(6 3 0 7 4 1 8 5 2 9))
+  (check-equal? (shuffle (range 10) (read-instructions "test4")) '(9 2 5 8 1 4 7 0 3 6)))
+
+(module+ main
+  (displayln "Part 1:")
+  (define instructions (read-instructions "input"))
+  (define deck (range 10007))
+  (time (index-of (shuffle deck instructions) 2019)))
+
+(define (deal-card deck-size card)
+  (- (sub1 deck-size) card))
+
+(define (cut-card deck-size n card)
+  (modulo (- card n) deck-size))
+
+(define (increment-card deck-size n card)
+  (modulo (* n card) deck-size))
+
+(define (execute-card deck-size instruction card)
+  (match instruction
+    ['deal (deal-card deck-size card)]
+    [(list 'cut n) (cut-card deck-size n card)]
+    [(list 'increment n) (increment-card deck-size n card)]))
+
+(define (shuffle-card deck-size instructions card)
+  (for/fold ([c card]) ([i instructions])
+    (execute-card deck-size i c)))
+
+(module+ main
+  (displayln "Part 1 (better):")
+  (time (shuffle-card 10007 instructions 2019)))
+
+(define (deal-card-inv deck-size card)
+  (- (sub1 deck-size) card))
+
+(define (cut-card-inv deck-size n card)
+  (modulo (+ card n) deck-size))
+
+(define (increment-card-inv deck-size n card)
+  (remainder (* card (modular-inverse n deck-size)) deck-size))
+
+(define (execute-card-inv deck-size instruction card)
+  (match instruction
+    ['deal (deal-card-inv deck-size card)]
+    [(list 'cut n) (cut-card-inv deck-size n card)]
+    [(list 'increment n) (increment-card-inv deck-size n card)]))
+
+(define (shuffle-card-inv deck-size reversed-instructions card)
+  (for/fold ([c card]) ([i reversed-instructions])
+    (execute-card-inv deck-size i c)))
+
+(module+ main
+  (displayln "Part 2:")
+  (define deck-size 119315717514047)
+  (define iterations 101741582076661)
+
+  ;; Operations are linear, we find the coefficients and apply them directly
+  (define x 2020)
+  (define y (shuffle-card-inv deck-size (reverse instructions) x))
+  (define z (shuffle-card-inv deck-size (reverse instructions) y))
+
+  (define a (modulo (* (- z y) (modular-inverse (- y x) deck-size)) deck-size))
+  (define b (modulo (- y (* a x)) deck-size))
+
+  (modulo (+ (* (modular-expt a iterations deck-size)
+                x)
+             (* (sub1 (modular-expt a iterations deck-size))
+                (modular-inverse (sub1 a) deck-size)
+                b))
+          deck-size))
--- a/2019/day22/input
+++ b/2019/day22/input
@ -0,0 +1,100 @@
+deal with increment 55
+cut -6984
+deal into new stack
+cut -2833
+deal with increment 75
+cut 2488
+deal with increment 54
+cut 9056
+deal with increment 52
+cut -2717
+deal with increment 4
+deal into new stack
+cut -852
+deal with increment 21
+cut -3041
+deal with increment 38
+cut -6871
+deal into new stack
+deal with increment 32
+cut 988
+deal with increment 29
+deal into new stack
+deal with increment 68
+cut 5695
+deal with increment 36
+cut -27
+deal with increment 33
+deal into new stack
+cut -1306
+deal with increment 30
+cut -4033
+deal with increment 28
+cut -442
+deal into new stack
+deal with increment 30
+cut -6295
+deal with increment 56
+cut -4065
+deal into new stack
+cut 5275
+deal with increment 64
+cut 9747
+deal into new stack
+deal with increment 63
+cut -3772
+deal with increment 61
+deal into new stack
+cut 1021
+deal with increment 73
+deal into new stack
+deal with increment 7
+cut -1232
+deal with increment 52
+cut -3439
+deal with increment 31
+cut 1128
+deal into new stack
+deal with increment 55
+deal into new stack
+deal with increment 39
+cut -3424
+deal with increment 11
+deal into new stack
+cut 4139
+deal with increment 15
+deal into new stack
+cut 5333
+deal with increment 16
+cut -6787
+deal with increment 39
+cut -5817
+deal into new stack
+deal with increment 62
+cut -2704
+deal with increment 64
+deal into new stack
+deal with increment 70
+cut 3436
+deal with increment 65
+cut -8686
+deal with increment 22
+cut -6190
+deal with increment 13
+cut -100
+deal into new stack
+cut -619
+deal into new stack
+cut 3079
+deal with increment 53
+cut 1725
+deal with increment 19
+cut 3440
+deal with increment 64
+cut 8578
+deal with increment 5
+cut 2341
+deal with increment 45
+cut 2217
+deal with increment 13
+deal into new stack
--- a/2019/day22/test1
+++ b/2019/day22/test1
@ -0,0 +1,3 @@
+deal with increment 7
+deal into new stack
+deal into new stack
--- a/2019/day22/test2
+++ b/2019/day22/test2
@ -0,0 +1,3 @@
+cut 6
+deal with increment 7
+deal into new stack
--- a/2019/day22/test3
+++ b/2019/day22/test3
@ -0,0 +1,3 @@
+deal with increment 7
+deal with increment 9
+cut -2
--- a/2019/day22/test4
+++ b/2019/day22/test4
@ -0,0 +1,10 @@
+deal into new stack
+cut -2
+deal with increment 7
+cut 8
+cut -4
+deal with increment 7
+cut 3
+deal with increment 9
+deal with increment 3
+cut -1
--- a/2019/day23/day23.rkt
+++ b/2019/day23/day23.rkt
@ -0,0 +1,30 @@
+#lang racket/base
+
+(require "../intcode.rkt"
+         racket/match
+         racket/list)
+
+(module+ test
+  (require rackunit))
+
+(define (get-packets vms)
+  (let loop ([packets (reverse (append* (map machine-outputs vms)))]
+             [h (hash)])
+    (match packets
+      ['() h]
+      [(list* addr x y r) (loop r (hash-update h addr (λ (lst) (append (list x y) lst)) '()))])))
+
+(define (part1 program)
+  (define vms (for/list ([i (in-range 50)])
+                (execute (start-machine program (list i)))))
+  (let loop ([vms vms])
+    (define packets (get-packets vms))
+    (if (hash-has-key? packets 255)
+        (cadr (hash-ref packets 255))
+        (loop
+         (for/list ([i (in-range 50)]
+                    [vm (in-list vms)])
+           (execute (struct-copy machine vm [inputs (hash-ref packets i '(-1))])))))))
+
+(module+ test
+  (check-equal? (part1 (parse-file "input")) 23266))
--- a/2019/day23/input
+++ b/2019/day23/input
--- a/2019/day24/day24.rkt
+++ b/2019/day24/day24.rkt
@ -0,0 +1,66 @@
+#lang racket
+
+(module+ test
+  (require rackunit))
+
+(define (read-input filename)
+  (for/set ([line (file->lines filename)]
+            [i (in-naturals)]
+            #:when #t
+            [c (in-string line)]
+            [j (in-naturals)]
+            #:when (eq? c #\#))
+    (make-rectangular j i)))
+
+(define (grid-size grid)
+  (define indices (flatten (map (λ (x) (list (real-part x) (imag-part x))) (set->list grid))))
+  (add1 (apply max indices)))
+
+(define (display-grid grid)
+  (define size (grid-size grid))
+  (for ([j (in-range size)])
+    (for ([i (in-range size)])
+      (if (set-member? grid (make-rectangular i j))
+          (printf "#")
+          (printf ".")))
+    (printf "~n")))
+
+(define (count-neighbours grid pos)
+  (for/sum ([step '(-i -1 +i 1)]
+            #:when (set-member? grid (+ pos step)))
+    1))
+
+(define (lives? grid pos)
+  (define n (count-neighbours grid pos))
+  (define alive (set-member? grid pos))
+  (cond
+    [(and alive (not (= 1 n))) #f]
+    [(and (not alive) (or (= 1 n) (= 2 n))) #t]
+    [else alive]))
+
+(define (step grid)
+  (define size (grid-size grid))
+  (for*/set ([i (in-range size)]
+             [j (in-range size)]
+             #:when (lives? grid (make-rectangular i j)))
+    (make-rectangular i j)))
+
+(define (biodiversity-rating grid)
+  (define size (grid-size grid))
+  (for*/sum ([i (in-range size)]
+             [j (in-range size)]
+             #:when (set-member? grid (make-rectangular i j)))
+    (expt 2 (+ i (* j size)))))
+
+(define (part1 filename)
+  (define grid (read-input filename))
+  (define final
+    (car (for/fold ([grids (list grid)])
+                   ([i (in-naturals)]
+                    #:break (member (car grids) (cdr grids)))
+           (cons (step (car grids)) grids))))
+  (biodiversity-rating final))
+
+(module+ test
+  (check-equal? (part1 "test") 2129920)
+  (check-equal? (part1 "input") 32573535))
--- a/2019/day24/input
+++ b/2019/day24/input
@ -0,0 +1,5 @@
+..#.#
+#.##.
+.#..#
+#....
+....#
--- a/2019/day24/test
+++ b/2019/day24/test
@ -0,0 +1,5 @@
+....#
+#..#.
+#..##
+..#..
+#....
--- a/2019/intcode.rkt
+++ b/2019/intcode.rkt
@ -0,0 +1,158 @@
+#lang racket/base
+
+(provide parse
+         parse-file
+         (struct-out machine)
+         start-machine
+         ascii->list
+         list->ascii
+         execute)
+
+(require racket/list
+         racket/string
+         racket/file
+         racket/match)
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;                                Program I/O                                  ;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(define (parse str)
+  (list->vector (map string->number (map string-trim (string-split str ",")))))
+
+(define (parse-file filename)
+  (parse (string-trim (file->string filename))))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;                                Instructions                                 ;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(struct instruction
+  (name
+   parameter-modes
+   inparams
+   outparams)
+  #:transparent)
+
+(define opcodes
+  (hash
+   99 'terminate
+   1 '(add 2 1)
+   2 '(mul 2 1)
+   3 '(input 0 1)
+   4 '(output 1 0)
+   5 '(jmpt 2 0)
+   6 '(jmpf 2 0)
+   7 '(lt 2 1)
+   8 '(eq 2 1)
+   9 '(rel 1 0)))
+
+(define (parse-instruction program pc relative-base)
+  (define opcode (vector-ref program pc))
+
+  (define-values (name nin nout)
+    (match (hash-ref opcodes (remainder opcode 100))
+      [(list name n m) (values name n m)]
+      [name (values name 0 0)]))
+
+  (define parameter-modes (make-hash))
+  (for/fold ([n (quotient opcode 100)])
+            ([i (in-naturals)]
+             #:break (= n 0))
+    (hash-set! parameter-modes i (remainder n 10))
+    (quotient n 10))
+
+  (define inparams
+    (for/list ([i (in-range nin)])
+      (match (hash-ref parameter-modes i 0)
+        [0 (vector-ref program (vector-ref program (+ pc i 1)))]
+        [1 (vector-ref program (+ pc i 1))]
+        [2 (vector-ref program (+ relative-base (vector-ref program (+ pc i 1))))])))
+
+  (define outparams
+    (for/list ([i (in-range nout)])
+      (match (hash-ref parameter-modes (+ nin i) 0)
+        [0 (vector-ref program (+ pc nin i 1))]
+        [1 (error "output parameter cannot be in immediate mode" name pc)]
+        [2 (+ relative-base (vector-ref program (+ pc nin i 1)))])))
+
+  (instruction name parameter-modes inparams outparams))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;                          Virtual machine interfaces                         ;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(struct machine
+  (program
+   inputs
+   pc
+   relative-base
+   terminated
+   outputs)
+  #:transparent
+  #:guard (lambda (program inputs pc relative-base terminated outputs name)
+            (when (not (<= 0 pc (vector-length program)))
+              (error "invalid program counter" pc))
+            (values program
+                    (preprocess-inputs inputs)
+                    pc
+                    relative-base
+                    terminated outputs)))
+
+(define (start-machine program inputs)
+  (machine program inputs 0 0 #f '()))
+
+(define (ascii->list str)
+  (map char->integer (string->list str)))
+
+(define (list->ascii lst)
+  (list->string (map integer->char lst)))
+
+(define (preprocess-inputs inputs)
+  (cond
+    [(list? inputs) inputs]
+    [(string? inputs) (ascii->list inputs)]
+    [else (error "unsupported input type: " inputs)]))
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;                          Virtual machine execution                          ;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(define (execute vm)
+  (define p (make-vector 10000 0))
+  (vector-copy! p 0 (machine-program vm))
+
+  (let loop ([pc (machine-pc vm)]
+             [relative-base (machine-relative-base vm)]
+             [inputs (machine-inputs vm)]
+             [outputs (machine-outputs vm)])
+    (define instr (parse-instruction p pc relative-base))
+    (define inparams (instruction-inparams instr))
+    (define outparams (instruction-outparams instr))
+    (define next-pc (+ pc (length inparams) (length outparams) 1))
+    
+    (match (instruction-name instr)
+      ['terminate (machine p inputs pc relative-base #t outputs)]
+      ['add (vector-set! p (car outparams) (apply + inparams))
+            (loop next-pc relative-base inputs outputs)]
+      ['mul (vector-set! p (car outparams) (apply * inparams))
+            (loop next-pc relative-base inputs outputs)]
+      ['input (if (empty? inputs)
+                  (machine p inputs pc relative-base #f outputs)
+                  (begin
+                    (vector-set! p (car outparams) (car inputs))
+                    (loop next-pc relative-base (cdr inputs) outputs)))]
+      ['output (loop next-pc relative-base inputs (cons (car inparams) outputs))]
+      ['jmpt (if (not (= 0 (car inparams)))
+                 (loop (cadr inparams) relative-base inputs outputs)
+                 (loop next-pc relative-base inputs outputs))]
+      ['jmpf (if (= 0 (car inparams))
+                 (loop (cadr inparams) relative-base inputs outputs)
+                 (loop next-pc relative-base inputs outputs))]
+      ['lt (vector-set! p (car outparams)
+                        (if (< (car inparams) (cadr inparams)) 1 0))
+           (loop next-pc relative-base inputs outputs)]
+      ['eq (vector-set! p (car outparams)
+                        (if (= (car inparams) (cadr inparams)) 1 0))
+           (loop next-pc relative-base inputs outputs)]
+      ['rel (loop next-pc (+ relative-base (car inparams)) inputs outputs)])))
				`@ -0,0 +1 @@`
				`1,0,0,3,1,1,2,3,1,3,4,3,1,5,0,3,2,9,1,19,1,9,19,23,1,23,5,27,2,27,10,31,1,6,31,35,1,6,35,39,2,9,39,43,1,6,43,47,1,47,5,51,1,51,13,55,1,55,13,59,1,59,5,63,2,63,6,67,1,5,67,71,1,71,13,75,1,10,75,79,2,79,6,83,2,9,83,87,1,5,87,91,1,91,5,95,2,9,95,99,1,6,99,103,1,9,103,107,2,9,107,111,1,111,6,115,2,9,115,119,1,119,6,123,1,123,9,127,2,127,13,131,1,131,9,135,1,10,135,139,2,139,10,143,1,143,5,147,2,147,6,151,1,151,5,155,1,2,155,159,1,6,159,0,99,2,0,14,0`
				`@ -0,0 +1 @@`
				3,225,1,225,6,6,1100,1,238,225,104,0,1102,46,47,225,2,122,130,224,101,-1998,224,224,4,224,1002,223,8,223,1001,224,6,224,1,224,223,223,1102,61,51,225,102,32,92,224,101,-800,224,224,4,224,1002,223,8,223,1001,224,1,224,1,223,224,223,1101,61,64,225,1001,118,25,224,101,-106,224,224,4,224,1002,223,8,223,101,1,224,224,1,224,223,223,1102,33,25,225,1102,73,67,224,101,-4891,224,224,4,224,1002,223,8,223,1001,224,4,224,1,224,223,223,1101,14,81,225,1102,17,74,225,1102,52,67,225,1101,94,27,225,101,71,39,224,101,-132,224,224,4,224,1002,223,8,223,101,5,224,224,1,224,223,223,1002,14,38,224,101,-1786,224,224,4,224,102,8,223,223,1001,224,2,224,1,223,224,223,1,65,126,224,1001,224,-128,224,4,224,1002,223,8,223,101,6,224,224,1,224,223,223,1101,81,40,224,1001,224,-121,224,4,224,102,8,223,223,101,4,224,224,1,223,224,223,4,223,99,0,0,0,677,0,0,0,0,0,0,0,0,0,0,0,1105,0,99999,1105,227,247,1105,1,99999,1005,227,99999,1005,0,256,1105,1,99999,1106,227,99999,1106,0,265,1105,1,99999,1006,0,99999,1006,227,274,1105,1,99999,1105,1,280,1105,1,99999,1,225,225,225,1101,294,0,0,105,1,0,1105,1,99999,1106,0,300,1105,1,99999,1,225,225,225,1101,314,0,0,106,0,0,1105,1,99999,1008,677,226,224,1002,223,2,223,1005,224,329,1001,223,1,223,107,677,677,224,102,2,223,223,1005,224,344,101,1,223,223,1107,677,677,224,102,2,223,223,1005,224,359,1001,223,1,223,1108,226,226,224,1002,223,2,223,1006,224,374,101,1,223,223,107,226,226,224,1002,223,2,223,1005,224,389,1001,223,1,223,108,226,226,224,1002,223,2,223,1005,224,404,1001,223,1,223,1008,677,677,224,1002,223,2,223,1006,224,419,1001,223,1,223,1107,677,226,224,102,2,223,223,1005,224,434,1001,223,1,223,108,226,677,224,102,2,223,223,1006,224,449,1001,223,1,223,8,677,226,224,102,2,223,223,1006,224,464,1001,223,1,223,1007,677,226,224,1002,223,2,223,1006,224,479,1001,223,1,223,1007,677,677,224,1002,223,2,223,1005,224,494,1001,223,1,223,1107,226,677,224,1002,223,2,223,1006,224,509,101,1,223,223,1108,226,677,224,102,2,223,223,1005,224,524,1001,223,1,223,7,226,226,224,102,2,223,223,1005,224,539,1001,223,1,223,8,677,677,224,1002,223,2,223,1005,224,554,101,1,223,223,107,677,226,224,102,2,223,223,1006,224,569,1001,223,1,223,7,226,677,224,1002,223,2,223,1005,224,584,1001,223,1,223,1008,226,226,224,1002,223,2,223,1006,224,599,101,1,223,223,1108,677,226,224,102,2,223,223,1006,224,614,101,1,223,223,7,677,226,224,102,2,223,223,1005,224,629,1001,223,1,223,8,226,677,224,1002,223,2,223,1006,224,644,101,1,223,223,1007,226,226,224,102,2,223,223,1005,224,659,101,1,223,223,108,677,677,224,1002,223,2,223,1006,224,674,1001,223,1,223,4,223,99,226
				`@ -0,0 +1 @@`
				3,8,1001,8,10,8,105,1,0,0,21,42,67,84,109,126,207,288,369,450,99999,3,9,102,4,9,9,1001,9,4,9,102,2,9,9,101,2,9,9,4,9,99,3,9,1001,9,5,9,1002,9,5,9,1001,9,5,9,1002,9,5,9,101,5,9,9,4,9,99,3,9,101,5,9,9,1002,9,3,9,1001,9,2,9,4,9,99,3,9,1001,9,2,9,102,4,9,9,101,2,9,9,102,4,9,9,1001,9,2,9,4,9,99,3,9,102,2,9,9,101,5,9,9,1002,9,2,9,4,9,99,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,101,2,9,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,1,9,4,9,99,3,9,1001,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1002,9,2,9,4,9,3,9,1001,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,99,3,9,102,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,1,9,9,4,9,3,9,101,1,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,101,2,9,9,4,9,3,9,101,1,9,9,4,9,3,9,101,1,9,9,4,9,3,9,101,2,9,9,4,9,99,3,9,1001,9,2,9,4,9,3,9,101,1,9,9,4,9,3,9,101,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,1001,9,2,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,1,9,9,4,9,3,9,102,2,9,9,4,9,3,9,102,2,9,9,4,9,3,9,101,1,9,9,4,9,99,3,9,102,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,101,2,9,9,4,9,3,9,1002,9,2,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,1,9,4,9,3,9,1002,9,2,9,4,9,3,9,101,1,9,9,4,9,3,9,102,2,9,9,4,9,3,9,1001,9,2,9,4,9,99
				`@ -0,0 +1 @@`
				1102,34463338,34463338,63,1007,63,34463338,63,1005,63,53,1101,0,3,1000,109,988,209,12,9,1000,209,6,209,3,203,0,1008,1000,1,63,1005,63,65,1008,1000,2,63,1005,63,904,1008,1000,0,63,1005,63,58,4,25,104,0,99,4,0,104,0,99,4,17,104,0,99,0,0,1101,0,30,1016,1101,37,0,1005,1101,362,0,1023,1101,0,20,1014,1101,39,0,1013,1102,34,1,1007,1101,682,0,1027,1102,664,1,1025,1102,1,655,1028,1101,0,26,1002,1102,1,38,1015,1101,669,0,1024,1101,0,28,1017,1102,1,21,1000,1101,0,27,1012,1102,1,29,1008,1102,1,23,1019,1101,0,24,1011,1101,685,0,1026,1102,646,1,1029,1102,1,369,1022,1101,0,31,1003,1102,1,36,1001,1101,0,0,1020,1102,1,35,1009,1101,32,0,1010,1101,0,1,1021,1102,33,1,1004,1101,22,0,1006,1102,1,25,1018,109,14,1205,6,197,1001,64,1,64,1105,1,199,4,187,1002,64,2,64,109,-4,21107,40,39,9,1005,1019,219,1001,64,1,64,1105,1,221,4,205,1002,64,2,64,109,9,1206,1,239,4,227,1001,64,1,64,1106,0,239,1002,64,2,64,109,-9,2101,0,-8,63,1008,63,26,63,1005,63,261,4,245,1106,0,265,1001,64,1,64,1002,64,2,64,109,-6,2108,37,1,63,1005,63,287,4,271,1001,64,1,64,1105,1,287,1002,64,2,64,109,15,21108,41,44,-2,1005,1017,307,1001,64,1,64,1106,0,309,4,293,1002,64,2,64,109,-16,1207,1,34,63,1005,63,327,4,315,1105,1,331,1001,64,1,64,1002,64,2,64,109,8,1208,-9,29,63,1005,63,347,1106,0,353,4,337,1001,64,1,64,1002,64,2,64,109,4,2105,1,8,1001,64,1,64,1105,1,371,4,359,1002,64,2,64,109,-22,1201,9,0,63,1008,63,27,63,1005,63,391,1106,0,397,4,377,1001,64,1,64,1002,64,2,64,109,18,21107,42,43,5,1005,1016,415,4,403,1106,0,419,1001,64,1,64,1002,64,2,64,109,-8,1201,2,0,63,1008,63,37,63,1005,63,441,4,425,1105,1,445,1001,64,1,64,1002,64,2,64,109,27,1205,-9,463,4,451,1001,64,1,64,1106,0,463,1002,64,2,64,109,-1,1206,-8,475,1105,1,481,4,469,1001,64,1,64,1002,64,2,64,109,-6,21101,43,0,-8,1008,1015,43,63,1005,63,507,4,487,1001,64,1,64,1106,0,507,1002,64,2,64,109,-15,2101,0,-3,63,1008,63,35,63,1005,63,531,1001,64,1,64,1106,0,533,4,513,1002,64,2,64,109,-2,2102,1,-6,63,1008,63,18,63,1005,63,553,1105,1,559,4,539,1001,64,1,64,1002,64,2,64,109,7,21102,44,1,3,1008,1016,44,63,1005,63,581,4,565,1105,1,585,1001,64,1,64,1002,64,2,64,109,-11,1202,7,1,63,1008,63,34,63,1005,63,609,1001,64,1,64,1105,1,611,4,591,1002,64,2,64,109,6,1202,1,1,63,1008,63,35,63,1005,63,637,4,617,1001,64,1,64,1106,0,637,1002,64,2,64,109,16,2106,0,4,4,643,1001,64,1,64,1106,0,655,1002,64,2,64,109,-1,2105,1,1,4,661,1106,0,673,1001,64,1,64,1002,64,2,64,109,5,2106,0,-1,1105,1,691,4,679,1001,64,1,64,1002,64,2,64,109,-24,1208,-2,26,63,1005,63,709,4,697,1105,1,713,1001,64,1,64,1002,64,2,64,109,-10,2102,1,6,63,1008,63,21,63,1005,63,735,4,719,1105,1,739,1001,64,1,64,1002,64,2,64,109,25,21108,45,45,-9,1005,1010,757,4,745,1106,0,761,1001,64,1,64,1002,64,2,64,109,-12,1207,-7,20,63,1005,63,777,1106,0,783,4,767,1001,64,1,64,1002,64,2,64,109,-13,2108,22,6,63,1005,63,799,1106,0,805,4,789,1001,64,1,64,1002,64,2,64,109,17,21102,46,1,0,1008,1011,45,63,1005,63,825,1105,1,831,4,811,1001,64,1,64,1002,64,2,64,109,-6,2107,21,1,63,1005,63,849,4,837,1105,1,853,1001,64,1,64,1002,64,2,64,109,-3,2107,27,0,63,1005,63,873,1001,64,1,64,1105,1,875,4,859,1002,64,2,64,109,12,21101,47,0,0,1008,1014,48,63,1005,63,899,1001,64,1,64,1105,1,901,4,881,4,64,99,21102,27,1,1,21101,0,915,0,1105,1,922,21201,1,42931,1,204,1,99,109,3,1207,-2,3,63,1005,63,964,21201,-2,-1,1,21101,942,0,0,1106,0,922,21202,1,1,-1,21201,-2,-3,1,21102,1,957,0,1106,0,922,22201,1,-1,-2,1106,0,968,22101,0,-2,-2,109,-3,2106,0,0
				`@ -0,0 +1 @@`
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				`@ -0,0 +1 @@`
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				`@ -0,0 +1 @@`
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