编程序求1!+2!+...+20!

可以使用循环结构和递归函数来实现。以下是两种不同的方法：

方法1：使用循环结构计算阶乘

result = 1  # 初始化结果为1
for i in range(1, 21):
    result *= i  # 依次乘以1~20
    print(i, '!=', result)

输出结果：

1 != 1
2 != 2
3 != 6
4 != 24
5 != 120
6 != 720
7 != 5040
8 != 40320
9 != 362880
10 != 3628800
11 != 39916800
12 != 479001600
13 != 6227020800
14 != 87178291200
15 != 1307674368000
16 != 20922789888000
17 != 355687428096000
18 != 6402373705728000
19 != 121645100408832000
20 != 2432902008176640000

方法2：使用递归函数计算阶乘

def factorial(n):
    if n == 1:
        return 1  # 1的阶乘为1
    else:
        return n * factorial(n-1)  # n的阶乘为n * (n-1)的阶乘

for i in range(1, 21):
    print(i, '!=', factorial(i))

输出结果同样为：

1 != 1
2 != 2
3 != 6
4 != 24
5 != 120
6 != 720
7 != 5040
8 != 40320
9 != 362880
10 != 3628800
11 != 39916800
12 != 479001600
13 != 6227020800
14 != 87178291200
15 != 1307674368000
16 != 20922789888000
17 != 355687428096000
18 != 6402373705728000
19 != 121645100408832000
20 != 2432902008176640000