Online PHP editor | vld for ZjH9j

@ 2014-03-25T18:33:08Z

<?php
function sum($arr) {
    if ( empty($arr) ) {
		return;
    }
    return $arr[0] + sum(array_slice($arr, 1));
}


function rev($str) {
    if ( ! $str ) {
    	return;
    }
    return rev(substr($str,1)) . $str{0};

}
echo sum(array(1,2,3,4,5));
echo rev('hola mundo');

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