day 8

2020/08.rkt

@@ -0,0 +1,34 @@
+#lang br
+(require racket/file rackunit racket/sequence racket/set)
+
+(define toks (for/list ([tok (in-port read (open-input-file "08.rktd"))])
+               tok))
+
+(struct $inst (name val))
+(define instructions (for/vector ([slice (in-slice 2 toks)])
+                       (apply $inst slice)))
+
+(define (run insts)
+  (let loop ([acc 0][ptr 0][visited null])
+    (cond
+      [(eq? ptr (vector-length insts)) (cons 'terminated acc)]
+      [(memq ptr visited) acc]
+      [else
+       (define next-visited (cons ptr visited))
+       (match (vector-ref insts ptr)
+         [($inst 'acc val) (loop (+ acc val) (add1 ptr) next-visited)]
+         [($inst 'jmp val) (loop acc (+ ptr val) next-visited)]
+         [($inst 'nop val) (loop acc (add1 ptr) next-visited)])])))
+
+(check-equal? (run instructions) 1818)
+
+(define (fix-bug insts)
+  (for/or ([(inst idx) (in-indexed insts)]
+           #:when (memq ($inst-name inst) '(jmp nop)))
+    (define new-insts (vector-copy insts))
+    (vector-set! insts idx ($inst (if (eq? ($inst-name inst) 'jmp) 'nop 'jmp) ($inst-val inst)))
+    (match (run new-insts)
+      [(cons 'terminated acc) acc]
+      [_ #false])))
+
+(check-equal? (fix-bug instructions) 187)

2020/08.rktd

@@ -0,0 +1,636 @@
+jmp +323
+acc +0
+acc -1
+acc +18
+jmp +601
+nop +531
+acc +7
+acc +46
+jmp +351
+acc +2
+jmp +532
+acc +20
+acc +15
+acc -7
+acc +27
+jmp +304
+acc +28
+acc +14
+jmp +593
+nop +448
+acc -2
+jmp +508
+acc +25
+acc +25
+jmp +1
+jmp +442
+acc +31
+acc -12
+acc +45
+jmp +1
+jmp +174
+nop +292
+jmp +93
+acc +29
+acc +46
+acc +23
+acc -5
+jmp +446
+acc +36
+jmp +115
+acc +27
+nop +186
+jmp +425
+jmp +390
+acc -9
+nop +560
+acc +2
+jmp +255
+acc -17
+acc +48
+jmp +131
+acc +37
+acc +6
+acc +0
+acc +0
+jmp +539
+acc +41
+acc +2
+acc +45
+acc +0
+jmp +291
+jmp +525
+acc -2
+acc +46
+acc -11
+jmp +381
+acc +17
+acc +7
+jmp +215
+acc -13
+acc +4
+jmp +1
+acc +50
+jmp -40
+acc -10
+acc +38
+jmp +256
+acc +31
+acc +5
+acc +1
+acc +40
+jmp -20
+acc +26
+acc +29
+nop +248
+nop +394
+jmp +169
+acc +15
+acc -1
+jmp +1
+acc -11
+jmp +99
+acc -12
+nop +485
+nop -2
+jmp +200
+acc +7
+acc +23
+acc +43
+acc +49
+jmp +245
+acc +6
+acc +36
+jmp +1
+nop +386
+jmp +130
+acc +4
+acc +12
+acc +33
+nop +443
+jmp +185
+acc -7
+jmp -72
+acc +5
+acc +24
+acc -9
+jmp -76
+jmp +286
+acc +50
+acc +20
+jmp -80
+acc +27
+jmp +41
+nop +465
+jmp +221
+jmp +1
+acc +9
+acc +9
+acc +0
+jmp -18
+acc +42
+nop +171
+acc +36
+jmp +57
+acc +25
+jmp +1
+jmp +248
+acc -1
+acc +11
+nop -22
+jmp +169
+acc -10
+acc -5
+jmp +274
+jmp +375
+jmp -94
+acc -17
+acc +32
+nop +175
+acc +35
+jmp +302
+jmp -34
+acc +0
+jmp +58
+acc +30
+acc +20
+acc +3
+acc +9
+jmp -125
+acc +41
+acc +24
+acc +6
+jmp -129
+acc +32
+acc +32
+acc +28
+acc +2
+jmp -148
+acc +5
+nop -129
+acc -18
+acc +21
+jmp +422
+acc +5
+acc +21
+acc +17
+jmp +112
+jmp +401
+acc +32
+jmp +192
+jmp -26
+acc +7
+acc +23
+nop +284
+acc -18
+jmp +426
+acc +19
+acc -5
+acc -10
+jmp -88
+nop +339
+acc -2
+jmp -11
+acc +1
+acc +26
+acc +3
+acc +47
+jmp +98
+acc -3
+jmp +124
+acc +28
+acc +10
+acc +45
+jmp +410
+acc -17
+acc +17
+acc -4
+jmp +1
+jmp +238
+jmp +1
+jmp +85
+nop +214
+jmp -151
+jmp -40
+acc +38
+jmp -123
+acc +23
+acc +46
+acc +29
+jmp +56
+jmp +89
+jmp -76
+nop -97
+acc +42
+acc +40
+jmp -181
+jmp -165
+acc +5
+acc +36
+acc +19
+jmp +106
+acc +43
+acc +48
+acc +26
+jmp -109
+acc +48
+acc +15
+jmp +315
+acc +18
+jmp +164
+jmp -26
+acc +18
+acc +6
+acc +18
+jmp -119
+jmp +1
+jmp +233
+acc +4
+acc +32
+acc +46
+jmp -168
+jmp +255
+acc +13
+acc +4
+jmp +236
+acc +2
+jmp -16
+acc +31
+jmp +155
+jmp -8
+acc +35
+acc +15
+jmp -211
+jmp +77
+jmp -163
+acc +24
+jmp +1
+acc +15
+nop +77
+jmp +291
+acc -3
+acc +7
+acc +42
+acc +7
+jmp +314
+acc +2
+acc +4
+jmp -66
+acc +9
+acc -4
+acc +49
+acc +28
+jmp -7
+jmp +174
+acc +3
+acc -19
+acc +15
+jmp -4
+acc +36
+jmp +289
+nop +219
+acc +36
+acc -13
+acc +11
+jmp -143
+acc +29
+acc +32
+acc +8
+jmp +283
+acc +41
+acc +24
+jmp -103
+acc +43
+jmp +110
+acc -18
+acc +14
+nop -255
+acc -1
+jmp -110
+acc +31
+acc +47
+nop +179
+nop +266
+jmp +185
+acc -7
+acc -6
+acc -16
+acc +12
+jmp +10
+acc +12
+jmp +1
+jmp -76
+jmp +278
+jmp +118
+acc +30
+acc +4
+acc -4
+jmp +9
+jmp +191
+acc +9
+acc +23
+jmp -133
+jmp -69
+acc +42
+acc +16
+jmp +276
+acc +12
+acc +49
+jmp +275
+jmp +159
+jmp +1
+acc +42
+jmp -14
+acc -16
+jmp +234
+jmp +107
+acc +35
+acc +39
+nop +36
+acc +6
+jmp -216
+acc +36
+acc +40
+jmp -133
+acc +26
+nop -210
+acc +46
+jmp +1
+jmp -13
+acc -4
+acc +19
+nop +208
+acc +27
+jmp +237
+nop +205
+acc +35
+jmp +59
+jmp +219
+acc +16
+acc +18
+jmp -249
+jmp +1
+acc +30
+acc +7
+jmp -220
+acc +12
+jmp -5
+acc +42
+acc +30
+acc +33
+jmp -121
+acc +47
+acc -7
+jmp +42
+jmp -7
+jmp -334
+jmp -360
+acc +0
+acc +50
+jmp -297
+jmp -4
+nop -51
+nop -291
+acc +47
+jmp -119
+acc -19
+acc +12
+jmp +98
+acc +19
+acc +10
+acc +32
+acc +0
+jmp +146
+acc +6
+acc -12
+acc +18
+acc +9
+jmp +26
+acc +10
+acc +1
+acc +24
+acc +11
+jmp +61
+acc +20
+jmp -273
+acc +47
+jmp +144
+acc -7
+acc +27
+jmp +123
+acc +50
+acc -8
+nop -182
+acc -15
+jmp -290
+acc -15
+nop -151
+acc +23
+acc +45
+jmp +93
+acc +32
+acc +39
+jmp -254
+acc +47
+acc +2
+acc +5
+acc -5
+jmp +92
+acc -5
+nop -428
+jmp +66
+acc +44
+nop -325
+nop +47
+jmp +35
+jmp +1
+acc +46
+acc +42
+acc +11
+jmp -117
+acc +14
+jmp -340
+jmp +117
+acc +3
+nop -179
+nop -65
+jmp -161
+nop -174
+acc +18
+jmp +172
+acc +44
+acc +28
+jmp -91
+jmp -362
+acc +46
+acc +17
+jmp +139
+acc +50
+acc +23
+jmp -92
+acc +0
+acc +12
+jmp -136
+acc +30
+acc -15
+jmp -285
+acc +42
+acc +11
+jmp -361
+nop +57
+acc -11
+jmp -216
+jmp +8
+acc +18
+jmp -418
+acc -8
+acc +31
+nop -4
+nop -31
+jmp -423
+acc +20
+jmp -264
+acc -7
+acc +11
+jmp -349
+jmp -22
+nop +46
+jmp +103
+acc -9
+nop -58
+acc +41
+jmp -134
+nop -50
+acc +12
+acc +13
+jmp -169
+jmp -495
+nop -74
+jmp -383
+acc +48
+nop -306
+acc +23
+acc +10
+jmp -315
+acc +7
+nop -342
+acc +23
+acc +28
+jmp -23
+jmp -297
+acc +47
+jmp -131
+acc -11
+acc +29
+jmp +1
+jmp -62
+acc +32
+acc +26
+jmp -205
+acc +34
+acc +43
+nop -309
+acc +37
+jmp -528
+nop +54
+jmp -149
+acc -13
+jmp -262
+acc +2
+nop -394
+acc +45
+jmp -116
+acc +13
+acc +0
+acc +6
+acc +45
+jmp -464
+jmp -343
+jmp -414
+acc -5
+acc +10
+jmp +62
+acc -1
+nop -313
+acc +35
+acc +49
+jmp -435
+acc +1
+acc +7
+jmp -50
+nop -415
+acc +9
+acc +22
+jmp -168
+nop -559
+jmp -367
+nop -141
+jmp -142
+jmp -370
+nop -74
+acc +2
+acc -19
+jmp -498
+acc +47
+acc +48
+acc +27
+acc +41
+jmp -182
+jmp -219
+acc +31
+jmp -128
+acc +44
+acc +18
+acc +17
+jmp -36
+jmp -182
+jmp +35
+jmp -184
+jmp +1
+acc +15
+jmp -239
+acc +19
+nop -50
+jmp -103
+acc +27
+acc +44
+jmp -8
+acc +5
+acc +36
+jmp -213
+acc -2
+acc +50
+nop -337
+jmp -252
+jmp -163
+acc -9
+jmp -433
+acc +2
+acc +22
+acc -19
+jmp -469
+jmp -45
+jmp -18
+acc +36
+acc +6
+acc +38
+jmp -475
+nop -281
+acc +36
+nop -575
+jmp -292
+acc -11
+acc +30
+nop -572
+acc +21
+jmp -235
+acc +3
+acc -16
+acc +8
+acc -9
+jmp -246
+acc +3
+acc +50
+jmp +1
+acc +49
+jmp +1