36 lines
805 B
PHP
36 lines
805 B
PHP
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<?php
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$input_file = '../inputs/day1.txt';
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if (file_exists($input_file)) {
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$input = file_get_contents($input_file);
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if ($input != null) {
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$nums = array_map(fn ($str) => (int)$str, array_filter(explode("\n", $input), 'is_numeric'));
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print 'Part 1 answer: ' . solve_part_one($nums) . "\n";
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print 'Part 2 answer: ' . solve_part_two($nums) . "\n";
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}
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}
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function solve_part_one(array $nums): int
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{
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$inc = 0;
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for ($i = 1; $i < count($nums); $i++) {
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if ($nums[$i] > $nums[$i - 1]) {
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$inc += 1;
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}
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}
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return $inc;
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}
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function solve_part_two(array $nums): int
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{
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$inc = 0;
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for ($i = 3; $i < count($nums); $i++) {
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$slider1 = $nums[$i] + $nums[$i - 1] + $nums[$i - 2];
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$slider2 = $nums[$i - 1] + $nums[$i - 2] + $nums[$i - 3];
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if ($slider1 > $slider2) {
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$inc += 1;
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}
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}
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return $inc;
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}
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