60 lines
911 B
PHP
60 lines
911 B
PHP
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<?php declare(strict_types=1);
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function readLines (): array
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{
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$fp = fopen("./input.txt", 'r');
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$lines = [];
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if ($fp)
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{
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while (($buffer = fgets($fp)))
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{
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$lines[] = $buffer;
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}
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fclose($fp);
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}
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return $lines;
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}
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function parseLists (): array
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{
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$arr1 = [];
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$arr2 = [];
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$lines = readLines();
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echo "Number of input lines: " . count($lines) . "\n";
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foreach ($lines as $line)
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{
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[$entry1, $entry2] = explode(' ', $line);
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$arr1[] = (int)$entry1;
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$arr2[] = (int)$entry2;
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}
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return [$arr1, $arr2];
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}
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function diffSum (array $list1, array $list2): int
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{
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sort($list1, SORT_NUMERIC);
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sort($list2, SORT_NUMERIC);
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$total = count($list1);
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$sum = 0;
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for ($i = 0; $i < $total; $i++)
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{
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$sum += abs($list1[$i] - $list2[$i]);
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}
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return $sum;
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}
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[$list1, $list2] = parseLists();
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$sumOfDifference = diffSum($list1, $list2);
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echo "Part 1: Total distance: $sumOfDifference\n";
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