# Created by PyCharm.
# User: zhangrxiang
# Date: 2017/1/11
# Time: 22:50
# File: 
# Project: python3
# Location: Wuxi

# 通过用户输入数字计算阶乘

# 获取用户输入的数字
num = int(input("请输入一个数字: "))
factorial = 1
sum = 0
# 查看数字是负数，0 或 正数
if num < 0:
    print("抱歉，负数没有阶乘")
elif num == 0:
    print("0 的阶乘为 1")
else:
    for i in range(1, num + 1):
        factorial = factorial * i
        sum += factorial
    print("%d 的阶乘为 %d" % (num, factorial))
    print("%d 到0的阶乘的和为 %d" % (num, sum))
