php设计求1+2!+3!+4!+5!+6!的程序并上机调试输出运行结果

以下是PHP代码实现1!到6!的计算，并输出结果：

<?php
function factorial($n){
    if($n == 0){
        return 1;
    }else{
        return $n * factorial($n-1);
    }
}

echo "1! = ".factorial(1)."\n";
echo "2! = ".factorial(2)."\n";
echo "3! = ".factorial(3)."\n";
echo "4! = ".factorial(4)."\n";
echo "5! = ".factorial(5)."\n";
echo "6! = ".factorial(6)."\n";
?>

运行结果：

1! = 1
2! = 2
3! = 6
4! = 24
5! = 120
6! = 720