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-rw-r--r--aoc2019/day-04/day-04.rkt39
1 files changed, 0 insertions, 39 deletions
diff --git a/aoc2019/day-04/day-04.rkt b/aoc2019/day-04/day-04.rkt
deleted file mode 100644
index 9518779..0000000
--- a/aoc2019/day-04/day-04.rkt
+++ /dev/null
@@ -1,39 +0,0 @@
-#lang racket
-
-(define (number->digits n [acc '()])
- (cond
- [(< n 10) (cons n acc)]
- [else (number->digits (quotient n 10) (cons (remainder n 10) acc))]))
-
-(define (always-increasing? xs)
- (match xs
- [(list _) #t]
- [(list* a b _) #:when (<= a b) (always-increasing? (cdr xs))]
- [_ #f]))
-
-(define (adjacent-pair? xs)
- (match xs
- [(list _) #f]
- [(list* a a _) a]
- [_ (adjacent-pair? (cdr xs))]))
-
-;; part 1
-(for/sum ([password (inclusive-range 125730 579381)]
- #:do [(define digits (number->digits password))]
- #:when ((conjoin always-increasing? adjacent-pair?) digits))
- 1)
-
-;; part 2
-(define (not-in-adjacent-triplet? xs)
- (match xs
- [(list a a c _ _ _) #:when (not (= a c)) #t]
- [(list b a a c _ _) #:when (not (or (= a b) (= a c))) #t]
- [(list _ b a a c _) #:when (not (or (= a b) (= a c))) #t]
- [(list _ _ b a a c) #:when (not (or (= a b) (= a c))) #t]
- [(list _ _ _ b a a) #:when (not (= a b)) #t]
- [_ #f]))
-
-(for/sum ([password (inclusive-range 125730 579381)]
- #:do [(define digits (number->digits password))]
- #:when ((conjoin always-increasing? adjacent-pair? not-in-adjacent-triplet?) digits))
- 1) \ No newline at end of file