88 lines
1.7 KiB
PHP
88 lines
1.7 KiB
PHP
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<?php
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namespace AdventOfCode21;
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class Day2 extends AbstractCommand
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{
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/**
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* {@inheritdoc}
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*/
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protected static int $day = 2;
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/**
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* {@inheritdoc}
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*/
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protected function part1(array $data): int
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{
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$depth = 0;
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$horizontal = 0;
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/** @var string $current */
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foreach ($data as $current) {
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/**
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* @var string $direction
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* @var int $distance
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*/
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[$direction, $distance] = explode(' ', $current);
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switch ($direction) {
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case 'forward':
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$horizontal += $distance;
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break;
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case 'down':
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$depth += $distance;
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break;
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case 'up':
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$depth -= $distance;
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break;
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}
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}
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return $depth * $horizontal;
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}
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/**
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* {@inheritdoc}
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*/
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protected function part2(array $data): int
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{
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$aim = 0;
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$depth = 0;
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$horizontal = 0;
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/** @var string $current */
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foreach ($data as $current) {
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/**
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* @var string $direction
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* @var int $distance
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*/
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[$direction, $distance] = explode(' ', $current);
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switch ($direction) {
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case 'forward':
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$horizontal += $distance;
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$depth += $distance * $aim;
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break;
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case 'down':
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$aim += $distance;
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break;
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case 'up':
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$aim -= $distance;
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break;
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}
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}
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return $horizontal * $depth;
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}
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}
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