advent_of_code_2022/day_4/part_1.php

18 lines
492 B
PHP

<?php
$elves = explode("\n", file_get_contents('./input.txt'));
echo count(
array_filter(
$elves,
static function($elf) {
[$section1, $section2] = array_map(static fn($section) => explode('-', $section), explode(',', $elf));
return
($section2[0] >= $section1[0] && $section2[1] <= $section1[1])
||
($section1[0] >= $section2[0] && $section1[1] <= $section2[1])
;
}
)
);