用函数方法编程求1!+2t...…+n!

以下是用函数方法编程求1!+2!+...+n!的Python代码：

def factorial(n):
    if n == 0:
        return 1
    else:
        return n * factorial(n-1)

def sum_factorial(n):
    sum = 0
    for i in range(1, n+1):
        sum += factorial(i)
    return sum

n = 5
print("1!+2!+...+n!的和为：", sum_factorial(n))