aoc/2021
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

day07: make a bit more idiomatic (i think)

Browse source
This commit is contained in:
Sijmen Schoon 2021-12-09 13:55:14 +01:00
parent d4aba82554
commit 299ccb33d0
Signed by: vijfhoek
GPG key ID: DAF7821E067D9C48
1 changed files with 16 additions and 22 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

32
day07.scm
View file

@ -7,31 +7,25 @@
(define numbers (map string->number (string-split (read-line) ","))) (define numbers (map string->number (string-split (read-line) ",")))
; PART 1 ; PART 1
(define sorted (sort numbers <)) (let* ((sorted (sort numbers <))
(define median (list-ref sorted (floor/ (length numbers) 2))) (median (list-ref sorted (floor/ (length numbers) 2)))
(part1
(define (part1) (foldl (lambda (x y) (+ x (abs (- y median))))
(foldl
(lambda (x y) (+ x (abs (- y median))))
0 0
numbers)) numbers)))
(format #t "part 1: ~A~%" part1))
; PART 2 ; PART 2
(define (triangular n) (/ (* n (+ n 1)) 2)) (define (triangular n) (/ (* n (+ n 1)) 2))
(define (part2- avg) (define (part2- avg)
(foldl (foldl (lambda (x y) (+ x (triangular (abs (- y avg)))))
(lambda (x y) (+ x (triangular (abs (- y avg)))))
0 0
numbers)) numbers))
(define avgCeil (ceiling/ (foldl + 0 numbers) (length numbers))) (let* ((len (length numbers))
(define avgFloor (floor/ (foldl + 0 numbers) (length numbers))) (sum (foldl + 0 numbers))
(avg-ceil (ceiling/ sum len))
(define (part2) (avg-floor (floor/ sum len))
(min (part2- avgCeil) (part2- avgFloor))) (part2 (min (part2- avg-ceil) (part2- avg-floor))))
(format #t "part 2: ~A~%" part2))
(format #t "part 1: ~A~%" (part1))
(format #t "part 2: ~A~%" (part2))