Online PHP editor | output for cdKnN

@ 2026-07-15T17:48:55Z

<?php

$fibonnacci = function (int $n, $previous2 = 0, $previous1 = 1) {
    if ($n <= 1) {
        return $previous2 + $previous1;
    }
    
    $closure = Closure::getCurrent();
    return $closure($n - 1, $previous1, $previous1 + $previous2);
};

print $fibonnacci(4);