src/2020/days/day-03.lisp @ 2848a4548adf
2023/01 and 2022/01
Also start porting my test data to the new account, since Twitter imploded and
apparently it's impossible for a website to store a goddamn username and
password in The Year of Our Lord 2023 so everyone just outsources auth all
the time, ugh.
author |
Steve Losh <steve@stevelosh.com> |
date |
Fri, 01 Dec 2023 11:05:43 -0500 |
parents |
ff7c8ed35992 |
children |
(none) |
(advent:defpackage* :advent/2020/03)
(in-package :advent/2020/03)
(defun count-trees (world drow dcol)
(destructuring-bind (rows cols) (array-dimensions world)
(iterate (for row :from 0 :below rows :by drow)
(for col :modulo cols :from 0 :by dcol)
(counting (char= #\# (aref world row col))))))
(define-problem (2020 3) (data read-2d-array) (257 1744787392)
(values (count-trees data 1 3)
(* (count-trees data 1 1)
(count-trees data 1 3)
(count-trees data 1 5)
(count-trees data 1 7)
(count-trees data 2 1))))
#; Scratch --------------------------------------------------------------------