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Add day 22 part 1

master
Clement Desmidt 2 years ago
parent
commit
1218e1c372
  1. 48
      day_22/part_1.php

48
day_22/part_1.php

@ -0,0 +1,48 @@
<?php
$cards = range(0, 10006);
$commands = explode("\n", file_get_contents('input.txt'));
function deal_into_new_stack(array $cards)
{
return array_reverse($cards);
}
function cut(array $cards, $n_card)
{
$slice = array_splice($cards, 0, $n_card);
return array_merge($cards, $slice);
}
function deal_with_increment(array $cards, $n)
{
$new_cards = [];
$deck_length = count($cards);
$card_index = 0;
$i = 0;
while($deck_length !== count($new_cards)) {
for (; $i < $deck_length; $i += $n) {
$new_cards[$i] = $cards[$card_index];
$card_index++;
}
$i = abs($deck_length - $i);
}
ksort($new_cards);
return $new_cards;
}
foreach ($commands as $command) {
if (strpos($command, 'deal with increment') === 0) {
$cards = deal_with_increment($cards, (int) substr($command, 20));
}
if (strpos($command, 'cut') === 0) {
$cards = cut($cards, (int) substr($command, 4));
}
if ('deal into new stack' === $command) {
$cards = deal_into_new_stack($cards);
}
}
echo array_search(2019, $cards, true);
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