求整數的階乘之和: s=1!+2!+3!+4!+...n!

求整數的階乘之和: s=1!+2!+3!+4!+...n!。

#!/usr/bin/python3



def factorial(num):
	fact = 1
	sum = 0
	if num < 0:
		print("負數沒有階乘！")
	elif num == 0:
		print("0的階乘爲1。")
	else:
		for i in range(1, num +1):
			fact = fact * i
			sum = sum + fact
		print("%d 的階乘是 %d, 階乘之和爲：%d" % (num, fact, sum))
		
num = int(input("請輸入一個整數："))
factorial(num)