Learn How to Calculate Factorial in Python: A Step-by-Step Guide with Examples

Factorial of N

Product of every number, between 1 and N

The factorial of a non-negative integer N, denoted by N!, is the product of all the positive integers up to N. For example, 5! (read as five factorial) equals 5 x 4 x 3 x 2 x 1 = 120.

To find the factorial of N, you can use a loop or a recursive function. Here’s an example of using a loop in Python:

“`
def factorial(n):
result = 1
for i in range(1, n+1):
result *= i
return result
“`

In this function, we initialize the result variable to 1 and then loop through the range from 1 to N (inclusive). For each iteration, we multiply the current value of result by the current value of i. Finally, we return the result.

Here’s an example of using a recursive function in Python:

“`
def factorial(n):
if n == 0:
return 1
else:
return n * factorial(n-1)
“`

In this function, we first check if n is 0 (the base case). If it is, we return 1. Otherwise, we return n times factorial(n-1), which is a recursive call to the same function with n-1 as the argument. The recursion continues until we reach the base case of n = 0.

Both of these methods will give you the same result for the factorial of N.

More Answers: