27 lines
655 B
PHP
27 lines
655 B
PHP
<?php
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function pandigital_less($number) {
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$array = count_chars($number,1);
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foreach(range(1,count($array)) as $char) {
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if( $array[ord($char)]!== 1) return false;
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}
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return true;
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}
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function is_prime($prime) {
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//if($prime%2 == 0) return false;
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$sqrt = sqrt($prime);
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for ($i = 3; $i <= $sqrt; $i+=2){
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if ($prime%$i == 0) return false;
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}
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return true;
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}
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//We don't need to check uneven numbers
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//Has to start with a 7 and therefor be 7 digits long
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for($var = 7000001; $var < 8000000; $var=$var+2) {
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if(is_prime($var) AND pandigital_less($var)) { $result = $var; }
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}
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echo $result; |