FINDING FACTORIAL OF A NUMBER IN PYTHON

How to find factorial of a number using python.

To find the factorial of a number in python we have two main methods as follows :

1. Using for loop in python

2. Using recursion

1. Using for loop in python

By using python for loop we can find the factorial of a number as follows : 

#choosing a number 

n = 5 

#setting a base value of factorial

factorial = 1

#checking conditions

if n < 0:

print ("factorial does not exist")

elif n == 0:

print ("factorial of 0 is 1")

else :

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

#incrementing the value of factorial

factorial = factorial*i

print (factorial)

2. Using recursion

The second way of finding the factorial of a number using recursion method is as follows: 

#defining function

def factorial(n):

if n == 0:

return 1

# recursion

return n*factorial(n-1)

answer = factorial(5)

#print factorial

print(answer)