Add 2021 advent - day 6.

2021/day6/p.rkt

@@ -0,0 +1,24 @@
+#lang racket
+
+(define first-initial-days 8)
+(define initial-days 6)
+
+(define (make-line t)
+  (map string->number (string-split t ",")))
+
+(define slist (make-line (read-line)))
+(define sv (make-vector 9))
+(for ([d slist]) (vector-set! sv d (add1 (vector-ref sv d))))
+
+(define (total-fish vec)
+  (for/sum ([v vec]) v))
+
+; input desired days HERE
+(for ([i (in-range 256)])
+	  (define holder (vector-ref sv 0))
+	  (for ([j (in-range 1 9)])
+			 (vector-set! sv (sub1 j) (vector-ref sv j)))
+	  (vector-set! sv 6 (+ (vector-ref sv 6) holder))
+	  (vector-set! sv 8 holder))
+
+(total-fish sv)

2021/day6/test1.txt

@@ -0,0 +1 @@
+3,4,3,1,2

2021/day6/test2.txt

@@ -0,0 +1 @@
+1,1,1,1,1,1,1,4,1,2,1,1,4,1,1,1,5,1,1,1,1,1,1,1,1,1,1,1,1,5,1,1,1,1,3,1,1,2,1,2,1,3,3,4,1,4,1,1,3,1,1,5,1,1,1,1,4,1,1,5,1,1,1,4,1,5,1,1,1,3,1,1,5,3,1,1,1,1,1,4,1,1,1,1,1,2,4,1,1,1,1,4,1,2,2,1,1,1,3,1,2,5,1,4,1,1,1,3,1,1,4,1,1,1,1,1,1,1,4,1,1,4,1,1,1,1,1,1,1,2,1,1,5,1,1,1,4,1,1,5,1,1,5,3,3,5,3,1,1,1,4,1,1,1,1,1,1,5,3,1,2,1,1,1,4,1,3,1,5,1,1,2,1,1,1,1,1,5,1,1,1,1,1,2,1,1,1,1,4,3,2,1,2,4,1,3,1,5,1,2,1,4,1,1,1,1,1,3,1,4,1,1,1,1,3,1,3,3,1,4,3,4,1,1,1,1,5,1,3,3,2,5,3,1,1,3,1,3,1,1,1,1,4,1,1,1,1,3,1,5,1,1,1,4,4,1,1,5,5,2,4,5,1,1,1,1,5,1,1,2,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,5,1,1,1,1,1,1,3,1,1,2,1,1