#!/usr/bin/env -S guile -s !# (use-modules (ice-9 regex) (ice-9 textual-ports) (srfi srfi-1)) (define red-max 12) (define green-max 13) (define blue-max 14) (define (read-lines port) (letrec ((loop (lambda (l ls) (if (eof-object? l) ls (loop (get-line port) (cons l ls)))))) (reverse (loop (get-line port) '())))) (define (valid-triplet? triplet) (let* ((zero (string-match "(.)" "0")) (red (string->number (match:substring (or (string-match "([0-9]+) red" triplet) zero) 1))) (green (string->number (match:substring (or (string-match "([0-9]+) green" triplet) zero) 1))) (blue (string->number (match:substring (or (string-match "([0-9]+) blue" triplet) zero) 1)))) (and (<= red red-max) (<= green green-max) (<= blue blue-max)))) (define (line-value line) (let* ((id-split (string-match "^Game ([0-9]+):(.*)$" line)) (id (string->number (match:substring id-split 1))) (rest (string-split (match:substring id-split 2) #\;)) (valid? (fold (lambda (x y) (and x y)) #t (map valid-triplet? rest)))) (if valid? id 0))) (let* ((port (open-input-file "2.txt")) (lines (read-lines port))) (close-port port) (display (fold + 0 (map line-value lines))))