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run code in 300+ PHP versions simultaneously
<?php $arr1 = [2,1,3,4,5,6,6,7]; $arr2 = [1,2,3,4,5,6,7]; $arr3 = [1,3,4,5,6,7]; $arr4 = [1,5,6,7,4,3,2]; sort($arr1); sort($arr2); sort($arr3); sort($arr4); $n = 7; $range = range(1,$n); var_dump($arr1 == $range); var_dump($arr2 == $range); var_dump($arr3 == $range); var_dump($arr4 == $range);

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27.03 ms | 406 KiB | 5 Q