Day 5

input/05.txt

@@ -0,0 +1,502 @@
+move 5 from 4 to 5
+move 2 from 5 to 8
+move 2 from 9 to 1
+move 2 from 9 to 1
+move 1 from 5 to 3
+move 10 from 5 to 8
+move 1 from 4 to 7
+move 1 from 1 to 2
+move 5 from 3 to 7
+move 1 from 2 to 8
+move 21 from 8 to 5
+move 13 from 5 to 7
+move 2 from 9 to 4
+move 1 from 7 to 4
+move 5 from 1 to 4
+move 1 from 5 to 7
+move 2 from 2 to 7
+move 1 from 3 to 2
+move 1 from 1 to 6
+move 7 from 5 to 9
+move 16 from 7 to 4
+move 7 from 9 to 3
+move 1 from 7 to 5
+move 1 from 3 to 8
+move 3 from 2 to 7
+move 1 from 8 to 9
+move 3 from 3 to 6
+move 21 from 4 to 9
+move 1 from 5 to 7
+move 4 from 4 to 9
+move 8 from 6 to 3
+move 6 from 7 to 1
+move 12 from 9 to 8
+move 6 from 7 to 2
+move 3 from 6 to 5
+move 1 from 6 to 9
+move 4 from 8 to 6
+move 3 from 8 to 5
+move 4 from 1 to 8
+move 4 from 6 to 1
+move 2 from 1 to 3
+move 1 from 5 to 8
+move 2 from 2 to 8
+move 5 from 8 to 3
+move 4 from 2 to 7
+move 5 from 8 to 1
+move 2 from 1 to 7
+move 1 from 8 to 2
+move 2 from 1 to 7
+move 11 from 9 to 2
+move 1 from 8 to 5
+move 2 from 9 to 4
+move 3 from 9 to 5
+move 2 from 5 to 1
+move 6 from 5 to 8
+move 2 from 4 to 2
+move 1 from 5 to 6
+move 7 from 1 to 8
+move 2 from 2 to 7
+move 13 from 8 to 1
+move 16 from 3 to 1
+move 3 from 2 to 1
+move 12 from 7 to 6
+move 15 from 1 to 8
+move 2 from 3 to 8
+move 16 from 1 to 2
+move 24 from 2 to 8
+move 1 from 1 to 5
+move 1 from 5 to 8
+move 3 from 6 to 7
+move 26 from 8 to 3
+move 20 from 3 to 9
+move 1 from 2 to 9
+move 16 from 9 to 3
+move 14 from 3 to 1
+move 13 from 1 to 6
+move 3 from 3 to 4
+move 3 from 9 to 4
+move 1 from 7 to 8
+move 5 from 8 to 2
+move 8 from 8 to 5
+move 18 from 6 to 1
+move 4 from 8 to 5
+move 6 from 4 to 1
+move 2 from 2 to 5
+move 5 from 3 to 8
+move 5 from 8 to 7
+move 2 from 5 to 8
+move 5 from 5 to 4
+move 3 from 2 to 8
+move 22 from 1 to 2
+move 1 from 1 to 2
+move 5 from 8 to 2
+move 2 from 5 to 2
+move 1 from 1 to 6
+move 5 from 5 to 2
+move 1 from 9 to 8
+move 5 from 4 to 1
+move 6 from 6 to 9
+move 3 from 1 to 9
+move 1 from 1 to 7
+move 8 from 9 to 6
+move 6 from 7 to 1
+move 5 from 6 to 5
+move 27 from 2 to 1
+move 4 from 5 to 7
+move 9 from 1 to 5
+move 1 from 9 to 1
+move 3 from 6 to 2
+move 9 from 2 to 1
+move 2 from 7 to 2
+move 1 from 8 to 7
+move 10 from 5 to 9
+move 1 from 9 to 7
+move 25 from 1 to 8
+move 6 from 7 to 4
+move 11 from 1 to 7
+move 3 from 8 to 1
+move 3 from 2 to 6
+move 3 from 8 to 9
+move 11 from 8 to 6
+move 1 from 2 to 6
+move 12 from 6 to 4
+move 13 from 4 to 5
+move 1 from 6 to 1
+move 3 from 7 to 5
+move 5 from 8 to 7
+move 1 from 7 to 1
+move 5 from 1 to 6
+move 3 from 6 to 4
+move 3 from 8 to 6
+move 2 from 5 to 2
+move 12 from 5 to 9
+move 5 from 6 to 2
+move 2 from 5 to 9
+move 6 from 4 to 9
+move 11 from 7 to 3
+move 1 from 2 to 5
+move 1 from 7 to 8
+move 1 from 5 to 7
+move 1 from 7 to 1
+move 1 from 8 to 1
+move 2 from 4 to 7
+move 2 from 6 to 8
+move 5 from 3 to 6
+move 2 from 7 to 2
+move 2 from 2 to 9
+move 1 from 2 to 9
+move 1 from 1 to 6
+move 35 from 9 to 7
+move 2 from 8 to 7
+move 3 from 3 to 8
+move 5 from 2 to 4
+move 3 from 3 to 7
+move 2 from 4 to 7
+move 4 from 6 to 5
+move 4 from 5 to 9
+move 3 from 4 to 5
+move 1 from 8 to 3
+move 4 from 9 to 8
+move 1 from 9 to 6
+move 38 from 7 to 2
+move 1 from 3 to 5
+move 1 from 1 to 7
+move 4 from 7 to 3
+move 3 from 6 to 1
+move 22 from 2 to 7
+move 1 from 5 to 8
+move 7 from 8 to 4
+move 8 from 2 to 8
+move 3 from 5 to 1
+move 4 from 3 to 9
+move 1 from 8 to 3
+move 1 from 3 to 7
+move 2 from 2 to 3
+move 5 from 8 to 9
+move 3 from 9 to 1
+move 2 from 1 to 7
+move 6 from 2 to 3
+move 6 from 3 to 1
+move 2 from 3 to 6
+move 1 from 6 to 1
+move 14 from 7 to 2
+move 4 from 1 to 6
+move 8 from 1 to 3
+move 4 from 3 to 6
+move 3 from 9 to 5
+move 1 from 8 to 6
+move 1 from 8 to 4
+move 9 from 7 to 1
+move 8 from 2 to 4
+move 4 from 2 to 9
+move 2 from 2 to 1
+move 3 from 5 to 8
+move 1 from 8 to 6
+move 1 from 7 to 8
+move 1 from 6 to 5
+move 3 from 9 to 5
+move 2 from 9 to 5
+move 4 from 3 to 9
+move 3 from 6 to 3
+move 3 from 6 to 9
+move 9 from 4 to 1
+move 1 from 9 to 8
+move 3 from 3 to 6
+move 2 from 7 to 4
+move 4 from 8 to 5
+move 7 from 5 to 6
+move 19 from 1 to 9
+move 5 from 9 to 3
+move 2 from 1 to 6
+move 1 from 4 to 6
+move 4 from 3 to 2
+move 21 from 9 to 7
+move 1 from 1 to 2
+move 1 from 9 to 1
+move 1 from 1 to 8
+move 16 from 7 to 6
+move 24 from 6 to 5
+move 7 from 4 to 5
+move 1 from 8 to 3
+move 2 from 2 to 8
+move 31 from 5 to 8
+move 1 from 4 to 6
+move 2 from 6 to 9
+move 1 from 7 to 4
+move 3 from 7 to 9
+move 1 from 4 to 8
+move 2 from 3 to 5
+move 1 from 2 to 3
+move 1 from 3 to 7
+move 1 from 7 to 9
+move 24 from 8 to 6
+move 1 from 8 to 1
+move 30 from 6 to 1
+move 2 from 5 to 2
+move 1 from 6 to 9
+move 6 from 9 to 7
+move 1 from 6 to 4
+move 1 from 4 to 6
+move 23 from 1 to 3
+move 21 from 3 to 4
+move 4 from 2 to 6
+move 3 from 6 to 1
+move 1 from 5 to 1
+move 4 from 1 to 9
+move 3 from 9 to 6
+move 8 from 1 to 6
+move 4 from 8 to 5
+move 2 from 7 to 5
+move 7 from 4 to 3
+move 3 from 4 to 9
+move 9 from 3 to 9
+move 1 from 7 to 6
+move 6 from 5 to 8
+move 14 from 6 to 2
+move 4 from 8 to 4
+move 7 from 4 to 5
+move 1 from 7 to 9
+move 6 from 4 to 3
+move 13 from 2 to 6
+move 5 from 3 to 7
+move 1 from 3 to 8
+move 1 from 8 to 2
+move 4 from 8 to 3
+move 6 from 6 to 4
+move 2 from 2 to 8
+move 5 from 4 to 7
+move 3 from 7 to 5
+move 1 from 7 to 9
+move 2 from 3 to 9
+move 3 from 7 to 3
+move 1 from 7 to 9
+move 1 from 7 to 9
+move 3 from 4 to 1
+move 6 from 6 to 1
+move 2 from 7 to 5
+move 1 from 3 to 5
+move 11 from 9 to 4
+move 9 from 4 to 5
+move 3 from 3 to 4
+move 1 from 3 to 9
+move 2 from 8 to 1
+move 9 from 1 to 8
+move 22 from 5 to 8
+move 2 from 1 to 3
+move 3 from 4 to 6
+move 14 from 8 to 9
+move 1 from 3 to 9
+move 19 from 9 to 3
+move 3 from 9 to 4
+move 2 from 7 to 2
+move 1 from 4 to 6
+move 1 from 3 to 8
+move 8 from 3 to 1
+move 2 from 9 to 6
+move 1 from 2 to 5
+move 3 from 4 to 9
+move 1 from 2 to 3
+move 20 from 8 to 3
+move 4 from 9 to 5
+move 1 from 4 to 2
+move 26 from 3 to 5
+move 1 from 8 to 3
+move 8 from 1 to 4
+move 1 from 3 to 7
+move 1 from 2 to 1
+move 1 from 1 to 6
+move 1 from 6 to 7
+move 4 from 5 to 3
+move 3 from 4 to 2
+move 5 from 5 to 3
+move 2 from 2 to 6
+move 3 from 3 to 5
+move 2 from 4 to 8
+move 5 from 3 to 9
+move 5 from 9 to 8
+move 19 from 5 to 9
+move 1 from 5 to 2
+move 2 from 7 to 1
+move 1 from 1 to 7
+move 1 from 7 to 4
+move 13 from 9 to 3
+move 8 from 6 to 2
+move 10 from 3 to 5
+move 14 from 5 to 4
+move 7 from 8 to 4
+move 1 from 6 to 2
+move 6 from 3 to 8
+move 4 from 9 to 7
+move 2 from 9 to 8
+move 1 from 7 to 1
+move 3 from 2 to 7
+move 1 from 5 to 3
+move 7 from 8 to 6
+move 5 from 6 to 2
+move 8 from 4 to 5
+move 3 from 5 to 8
+move 3 from 8 to 6
+move 5 from 7 to 9
+move 5 from 3 to 6
+move 1 from 9 to 4
+move 17 from 4 to 7
+move 1 from 8 to 1
+move 12 from 7 to 8
+move 3 from 1 to 4
+move 2 from 4 to 6
+move 8 from 6 to 1
+move 4 from 6 to 3
+move 1 from 7 to 8
+move 5 from 5 to 8
+move 4 from 7 to 1
+move 3 from 2 to 6
+move 2 from 5 to 1
+move 6 from 1 to 6
+move 4 from 3 to 5
+move 4 from 5 to 3
+move 1 from 4 to 8
+move 3 from 3 to 2
+move 17 from 8 to 4
+move 6 from 6 to 3
+move 14 from 4 to 9
+move 1 from 3 to 8
+move 1 from 7 to 4
+move 3 from 8 to 3
+move 5 from 2 to 5
+move 6 from 1 to 7
+move 2 from 6 to 4
+move 4 from 5 to 7
+move 1 from 1 to 5
+move 1 from 6 to 3
+move 10 from 7 to 4
+move 1 from 5 to 4
+move 1 from 2 to 3
+move 15 from 4 to 5
+move 3 from 3 to 1
+move 6 from 2 to 6
+move 1 from 2 to 3
+move 2 from 4 to 7
+move 2 from 7 to 8
+move 1 from 4 to 2
+move 2 from 1 to 7
+move 1 from 7 to 2
+move 12 from 9 to 1
+move 4 from 9 to 5
+move 4 from 6 to 2
+move 1 from 7 to 3
+move 6 from 2 to 4
+move 1 from 8 to 5
+move 2 from 4 to 2
+move 11 from 1 to 7
+move 3 from 1 to 4
+move 17 from 5 to 6
+move 15 from 6 to 4
+move 1 from 8 to 9
+move 10 from 4 to 1
+move 1 from 3 to 9
+move 2 from 6 to 5
+move 1 from 2 to 6
+move 4 from 5 to 6
+move 4 from 1 to 2
+move 6 from 6 to 7
+move 2 from 2 to 6
+move 9 from 4 to 9
+move 6 from 1 to 2
+move 3 from 4 to 1
+move 10 from 9 to 8
+move 4 from 2 to 1
+move 1 from 1 to 2
+move 5 from 8 to 6
+move 1 from 2 to 7
+move 1 from 9 to 4
+move 2 from 6 to 9
+move 13 from 7 to 2
+move 5 from 7 to 5
+move 2 from 5 to 2
+move 1 from 4 to 5
+move 4 from 8 to 4
+move 17 from 2 to 6
+move 3 from 4 to 6
+move 2 from 9 to 1
+move 7 from 6 to 8
+move 1 from 5 to 2
+move 1 from 4 to 1
+move 2 from 9 to 4
+move 1 from 3 to 9
+move 4 from 3 to 7
+move 2 from 8 to 5
+move 3 from 7 to 5
+move 10 from 5 to 8
+move 2 from 2 to 4
+move 6 from 1 to 2
+move 4 from 6 to 3
+move 8 from 2 to 6
+move 1 from 7 to 4
+move 5 from 4 to 5
+move 7 from 6 to 7
+move 5 from 3 to 5
+move 5 from 5 to 2
+move 4 from 8 to 1
+move 6 from 1 to 6
+move 3 from 3 to 2
+move 22 from 6 to 2
+move 1 from 9 to 7
+move 8 from 8 to 6
+move 1 from 7 to 6
+move 2 from 5 to 7
+move 4 from 8 to 5
+move 7 from 6 to 7
+move 2 from 6 to 4
+move 14 from 2 to 1
+move 7 from 1 to 3
+move 12 from 7 to 3
+move 1 from 4 to 3
+move 2 from 5 to 8
+move 2 from 8 to 1
+move 1 from 4 to 3
+move 6 from 2 to 9
+move 6 from 9 to 2
+move 2 from 2 to 7
+move 6 from 7 to 5
+move 13 from 3 to 5
+move 5 from 2 to 6
+move 5 from 6 to 1
+move 2 from 3 to 6
+move 1 from 6 to 5
+move 1 from 6 to 1
+move 3 from 1 to 9
+move 6 from 2 to 7
+move 1 from 2 to 3
+move 24 from 5 to 2
+move 7 from 3 to 7
+move 13 from 7 to 9
+move 4 from 1 to 9
+move 4 from 1 to 6
+move 1 from 5 to 6
+move 16 from 9 to 5
+move 1 from 6 to 4
+move 1 from 5 to 2
+move 5 from 1 to 3
+move 11 from 2 to 1
+move 4 from 9 to 6
+move 1 from 4 to 7
+move 2 from 3 to 4
+move 6 from 6 to 9
+move 1 from 1 to 3
+move 2 from 9 to 4
+move 1 from 7 to 9
+move 4 from 2 to 9
+move 8 from 9 to 2
+move 3 from 3 to 2
+move 1 from 9 to 4
+move 5 from 1 to 7
+move 1 from 4 to 8
+move 2 from 1 to 9
+move 1 from 8 to 7
+move 6 from 5 to 3
+move 1 from 5 to 1
+move 5 from 2 to 3
+move 4 from 1 to 5
+move 4 from 7 to 1
+move 8 from 5 to 8

lib.rkt

@@ -306,8 +306,8 @@
   (vector-ref vec (sub1 (vector-length vec))))
 
 ;; vector-ref* : (vectorof any) -> number -> any -> any
-;; Same as list-ref, except a default value is provided
+;; Same as vector-ref, except a default value is provided
-;; if the index is beyond the length of the list.
+;; if the index is beyond the length of the vector.
 (define (vector-ref* vec pos failure-result)
   (if (>= pos (vector-length vec))
       failure-result

src/05.rkt

@@ -0,0 +1,52 @@
+#lang curly-fn racket
+
+(require "../lib.rkt")
+
+(define input
+  (for/list ([instr (problem-input 5)])
+    (map string->number (regexp-match* #px"\\d+" instr))))
+
+;; crates? = (listof symbol?)
+;; supplies? = (listof crates?)
+;; stack? = (integer-in 1 9)
+
+;; initial : supplies?
+(define initial
+  (list '(||) ;; dummy stack since they start at 1
+        '(W L S)
+        '(Q N T J)
+        '(J F H C S)
+        '(B G N W M R T)
+        '(B Q H D S L R T)
+        '(L R H F V B J M)
+        '(M J N R W D)
+        '(J D N H F T Z B)
+        '(T F B N Q L H)))
+
+;; squish : crates? -> string?
+(define (squish symbols)
+  (~>> symbols
+      (map symbol->string)
+      (apply string-append)))
+
+;; move : supplies? (crates? -> crates?) -> number? stack? stack? -> supplies?
+(define ((move crates f) num from to)
+  (define transfer (take (list-ref crates from) num))
+  (~> crates
+      (list-update from #{drop % num})
+      (list-update to #{append (f transfer) %})))
+
+;; moves : (crates? -> crates?) -> string?
+(define (moves f)
+  (for/fold ([crates initial]
+             #:result (squish (map first crates)))
+            ([instr input])
+    (apply (move crates f) instr)))
+
+(define part1
+  (moves reverse))
+  
+(define part2
+  (moves identity))
+
+(show-solution part1 part2)