Initial commit

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))