31 lines
875 B
Scheme
31 lines
875 B
Scheme
|
(import (chicken io))
|
||
|
|
(import (chicken format))
|
||
|
|
(import srfi-1)
|
||
|
|
|
||
|
|
(define (parse inputs)
|
||
|
|
(let ((line (read-line)))
|
||
|
|
(if (not (eof-object? line))
|
||
|
|
(parse (cons (string->number line) inputs))
|
||
|
|
inputs)))
|
||
|
|
|
||
|
|
(define (inc-if cond num)
|
||
|
|
(if cond (+ num 1) num))
|
||
|
|
|
||
|
|
(define (part1 inputs previous counter)
|
||
|
|
(if (not (null? inputs))
|
||
|
|
(let ((head (car inputs)))
|
||
|
|
(part1 (cdr inputs) head (inc-if (<= head previous) counter)))
|
||
|
|
counter))
|
||
|
|
|
||
|
|
|
||
|
|
(define (part2 inputs previous counter)
|
||
|
|
(if (not (eq? inputs '()))
|
||
|
|
(let ((sum (apply + (take-right! inputs 3))))
|
||
|
|
(part2 (cdr inputs) sum (inc-if (<= sum previous) counter)))
|
||
|
|
counter))
|
||
|
|
|
||
|
|
(let ((inputs (parse '())))
|
||
|
|
(format #t "inputs = ~A~%" inputs)
|
||
|
|
(format #t "part1 = ~A~%" (part1 inputs 0 0))
|
||
|
|
(format #t "part2 = ~A~%" (part2 inputs 0 0)))
|