~php
<?
if ($n <= 0) echo "잘못된 값이 입력되었 습니다.";
elseif ($n == 1 or $n == 2)
{
echo "1";
exit();
}
$result = pibo($n);
echo $result;
?>
<?
function pibo($n)
{
if ($n == 1 or $n == 2) return 1;
return (pibo($n-1) + pibo($n-2));
}
?>