def factorial(n):

prod = 1

for i in range(1, n+1):

prod *= i

return prod

def guess_factorial():

n = int(input(“Guess a number between 1 and 1000: “))

print(“The factorial of”, n, “is”, factorial(n))

def welcome():

print(“This Python program will calculate the factorial of any number between 1 and 1000.”)

print(“You are provided with two functions: one to calculate the factorials, and another to help you guess values for the input. A third function returns a message when a factorial exceeds 1000.”)

welcome()

fact_dict = {}

def factorial(n):

if n == 1:

return 1

else:

print(“Now we’re going to calculate {}! That’s a big number.”.format(n))

product = (n * factorial(n-1))

print(“{}! is equal to {}.”.format(n, product))

if product > 1000:

return ‘Over a thousand.’

else:

return product

print(“This function will calculate any factorial up to 1000.”)

print(“Please enter an integer between 1 and 1000.”)

def num_user():

n = int(input())

def calculate_factorial():

n = int(input(“Enter a number between 1 and 1000: “))

fact = 1

while n > 0:

fact *= n

n -= 1

return fact

import math

def calc_factorial(x):

“””This is a recursive function

to find the factorial of an integer”””

if x == 1:

return 1

else:

return (x * calc_factorial(x-1))

num = 4

print(“The factorial of”, num, “is”, calc_factorial(num))

def factorial(x):

“””This is a recursive function

to find the factorial of an integer”””

if x == 1:

return 1

else:

return (x * factorial(x-1))

num = 3

print(“The factorial of”, num, “is”, factorial(num))

First, you need to import the math module.

import math

def factorial(n):

“””Return the factorial of n, an exact integer >= 0.

If the result is small enough to fit in an int, return an int.

Else return a long.

>>> [factorial(n) for n in range(6)]

[1, 1, 2, 6, 24, 120]

>>> [factorial(long(n)) for n in range(6)]

[1, 1, 2, 6, 24, 120]

>>> factorial(30)

265252859812191058636308480000000L

>>> factorial(30L)

265252859812191058636308480000000L

>>> factorial(-1)

Traceback (most recent call last):

…

ValueError: n must be >= 0

Factorials of floats are OK, but the float must be an exact integer:

>>> factorial(30.1)

Traceback (most recent call last):

…

ValueError: n must be exact integer”””

if not n >= 0: