42 lines
1.1 KiB
PHP
42 lines
1.1 KiB
PHP
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<?php
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$wire_paths = explode("\n", file_get_contents('input.txt'));
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$wires = [];
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function mark_wire_in_grid(string $wire)
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{
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$steps = 0;
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$mapping = [
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'U' => [0,1],
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'D' => [0,-1],
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'L' => [-1,0],
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'R' => [1,0],
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];
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$points = [];
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$path = explode(',', $wire);
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$current_point_x = 0;
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$current_point_y = 0;
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foreach ($path as $dot) {
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$direction = $dot[0];
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$number = (int) substr($dot, 1);
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for ($t = 0; $t < $number; $t++) {
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$current_point_x += $mapping[$direction][0];
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$current_point_y += $mapping[$direction][1];
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$points["$current_point_x,$current_point_y"] = ++$steps;
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}
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}
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return $points;
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}
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foreach ($wire_paths as $i => $wire_path) {
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$wires[] = mark_wire_in_grid($wire_path);
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}
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$common_points = array_intersect_key($wires[0], $wires[1]);
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$total_steps = [];
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foreach ($common_points as $coordinates => $steps) {
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$total_steps[$coordinates] = $wires[0][$coordinates] + $wires[1][$coordinates];
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}
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echo sprintf('Le plus court pas : %s', min($total_steps));
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