3v4l.org

run code in 300+ PHP versions simultaneously
<?php function rev($str) { if ( ! $str ) { return; } return rev(substr($str,1)) . $str{0}; } function sum($arr) { if ( empty($arr) ) { return; } return sum(array_shift($arr)) + $arr[0]; } $a = array(5,4,7,8,9,3); echo sum($a); echo rev('hola mundos ninos');

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31.2 ms | 402 KiB | 5 Q