advent_of_code_2020/day_2/part_2.php
2020-12-03 12:27:47 +01:00

20 lines
483 B
PHP

<?php
$passwords = explode("\n", file_get_contents('input.txt'));
$number_of_good_passwords = 0;
foreach ($passwords as $password) {
$parts = explode(' ', $password);
if (count($parts) === 3) {
[$min, $max] = explode('-', $parts[0]);
$letter = $parts[1][0];
$word = $parts[2];
if ($word[$min-1] === $letter xor $word[$max-1] === $letter) {
$number_of_good_passwords++;
}
}
}
echo $number_of_good_passwords;
exit(0);