choice = int(input("Enter a number: "))
def fact(num):
if(num == 0):
return 1
return num * fact(num-1)
factorial = fact(choice)
print("The factorial of %d is %d." % (choice, factorial))
Y2hvaWNlID0gaW50KGlucHV0KCJFbnRlciBhIG51bWJlcjogIikpCgpkZWYgZmFjdChudW0pOgogICAgaWYobnVtID09IDApOgogICAgICAgIHJldHVybiAxCiAgICByZXR1cm4gbnVtICogZmFjdChudW0tMSkKCmZhY3RvcmlhbCA9IGZhY3QoY2hvaWNlKQpwcmludCgiVGhlIGZhY3RvcmlhbCBvZiAlZCBpcyAlZC4iICUgKGNob2ljZSwgZmFjdG9yaWFsKSk=