diff options
Diffstat (limited to 'aoc2023-racket/day-06/day-06.rkt')
-rw-r--r-- | aoc2023-racket/day-06/day-06.rkt | 32 |
1 files changed, 0 insertions, 32 deletions
diff --git a/aoc2023-racket/day-06/day-06.rkt b/aoc2023-racket/day-06/day-06.rkt deleted file mode 100644 index 53ca9ee..0000000 --- a/aoc2023-racket/day-06/day-06.rkt +++ /dev/null @@ -1,32 +0,0 @@ -#lang racket - -(require advent-of-code - threading) - -(match-define (list times distances) - (~> (open-aoc-input (find-session) 2023 6 #:cache #true) port->lines)) - -;; part 1 -(define get-numbers (λ~> string-split (map string->number _) rest)) -(define (find-bound race-time dist button-time step) - (if (< dist (* button-time (- race-time button-time))) - button-time - (find-bound race-time dist (+ step button-time) step))) - -(define (lower-bound rtime dist) - (find-bound rtime dist 1 1)) -(define (upper-bound rtime dist) - (find-bound rtime dist rtime -1)) - -(for/fold ([acc 1]) - ([race-time (in-list (get-numbers times))] - [distance (in-list (get-numbers distances))]) - (* acc (add1 (- (upper-bound race-time distance) (lower-bound race-time distance))))) - -;; part 2 - -(define unkern (λ~>> get-numbers (apply ~a) string->number)) -(define big-time (unkern times)) -(define big-distance (unkern distances)) - -(add1 (- (upper-bound big-time big-distance) (lower-bound big-time big-distance))) |