Day 13
author |
Steve Losh <steve@stevelosh.com> |
date |
Sun, 16 Dec 2018 21:30:28 -0500 |
parents |
a19c9e1fd077 |
children |
5b5c61ad8d2b |
(defpackage :advent/2018/03 #.cl-user::*advent-use*)
(in-package :advent/2018/03)
(named-readtables:in-readtable :interpol-syntax)
(defstruct claim id left right top bottom)
(define-with-macro claim id left right top bottom)
(defun parse-claim (line)
(ppcre:register-groups-bind
((#'parse-integer id col row width height))
(#?r"#(\d+) @ (\d+),(\d+): (\d+)x(\d+)" line)
(make-claim :id id
:left col
:top row
:right (+ col width)
:bottom (+ row height))))
(defun claims-intersect-p (claim1 claim2)
(with-claim (claim1 id1 left1 right1 top1 bottom1)
(with-claim (claim2 id2 left2 right2 top2 bottom2)
(not (or (<= right2 left1)
(<= right1 left2)
(>= top2 bottom1)
(>= top1 bottom2))))))
(defun make-fabric (claims)
(let ((fabric (make-array (list 1000 1000) :initial-element 0)))
(dolist (claim claims)
(with-claim (claim)
(do-range ((row top bottom)
(col left right))
(incf (aref fabric row col)))))
fabric))
(define-problem (2018 3) (data read-lines)
(let* ((claims (mapcar #'parse-claim data))
(fabric (make-fabric claims)))
(values
(iterate (for uses :in-array fabric)
(counting (> uses 1)))
(claim-id (first (unique claims :test #'claims-intersect-p))))))
(1am:test test-2018/03
(multiple-value-bind (part1 part2) (run)
(1am:is (= 107663 part1))
(1am:is (= 1166 part2))))