23 lines
570 B
PHP
23 lines
570 B
PHP
<?php
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function pandigital($number) {
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$array = count_chars($number,1);
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ksort($array);
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if($array == array(49=>1,50=>1,51=>1,52=>1,53=>1,54=>1,55=>1,56=>1,57=>1)) { return true;} else { return false; }
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}
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$products = [];
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for($a = 1; $a <= 2500; $a++) {
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for($b = 1; $b <= 2500; $b++) {
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$p = $a*$b;
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$str = (string)$a.$b.$p;
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if(strlen($str) == 9 && pandigital($str))
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{
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$products[] = $p;
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echo "Found $a*$b=$p\n";
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}
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}
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}
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$products = array_unique($products);
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echo array_sum($products).PHP_EOL; |