3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a = []; $x = 63; for ($x = 0; $x < 10000; $x++) { $a[] = substr($x, 0, 1); $a[] = substr($x, 1, 1); // $x_arr = str_split($x); // $a[] = $x_arr[0]; // $a[] = $x_arr[1]; } echo count($a);

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72.78 ms | 402 KiB | 5 Q