25 每日一更

# coding=utf-8
# Created by danding at 2019/10/31

from math import *

def jiechenghe(num):
    list = []
    k = 1
    for i in range(1,num+1):
        k = k*i
        list.append(k)
    sum = 0
    for i in list:
        sum += i

    print('前{}项的阶乘和是:{}'.format(num,sum))

while 1:
    try:
        num = input('提示:输入"q"退出程序。
请输入前几项数字的阶乘和:')
        if num.lower()=='q':
            break
        num = int(num)
    except:
        print('请输入数！')
        continue
    jiechenghe(num)