26 lines
766 B
PHP
26 lines
766 B
PHP
<?php
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function lookup($r,$c) {
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$table = array(
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array(0, 3, 1, 7, 5, 9, 8, 6, 4, 2),
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array(7, 0, 9, 2, 1, 5, 4, 8, 6, 3),
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array(4, 2, 0, 6, 8, 7, 1, 3, 5, 9),
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array(1, 7, 5, 0, 9, 8, 3, 4, 2, 6),
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array(6, 1, 2, 3, 0, 4, 5, 9, 7, 8),
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array(3, 6, 7, 4, 2, 0, 9, 5, 8, 1),
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array(5, 8, 6, 9, 7, 2, 0, 1, 3, 4),
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array(8, 9, 4, 5, 3, 6, 2, 0, 1, 7),
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array(9, 4, 3, 8, 6, 1, 7, 2, 0, 5),
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array(2, 5, 8, 1, 4, 3, 6, 7, 9, 0),
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);
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return $table[$r][$c];
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}
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function isDammValid($input) {
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return array_reduce(str_split($input), "lookup", 0) == 0;
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}
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foreach(array("5724", "5727", "112946", "112949") as $i) {
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echo "{$i} is ".(isDammValid($i) ? "valid" : "invalid")."<br>";
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}
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?>
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