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diff --git a/racket/aoc2015/day-05/day-05.rkt b/racket/aoc2015/day-05/day-05.rkt
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+++ b/racket/aoc2015/day-05/day-05.rkt
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+#lang racket
+(require "../../jj-aoc.rkt"
+         threading)
+
+(define strs (port->lines (open-day 5 2015)))
+
+;; part 1
+(define (at-least-three-vowels? str)
+  (~>> str (regexp-replace* #px"[^aeiou]" _ "") string-length (<= 3)))
+
+(define (at-least-one-pair? str)
+  (regexp-match? #px"(.)\\1{1,}" str))
+
+(define (no-forbidden-pairs? str)
+  (~>> (list "ab" "cd" "pq" "xy") (ormap (λ~>> (string-contains? str))) not))
+
+(define (nice? str)
+  (~>> (list at-least-three-vowels? at-least-one-pair? no-forbidden-pairs?) (andmap (λ (f) (f str)))))
+
+(count nice? strs)
+
+;; part 2
+(define (repeating-pair? str)
+  (regexp-match? #px"(..).*\\1" str))
+
+(define (symmetry? str)
+  (regexp-match? #px"(.).\\1" str))
+
+(define (new-nice? str)
+  (~>> (list repeating-pair? symmetry?) (andmap (λ (f) (f str)))))
+
+(count new-nice? strs)