# Python Program - Find Factorial of a Number

The factorial of a positive integer is the multiplication of all positive integer less than or equal to that number.

$factorial$ $of$ $number$ $n$ = $n! = n(n-1)(n-2)...1$

### For Example:

$5! = 5\times4\times3\times2\times1 = 120$

$4! = 4\times3\times2\times1 = 24$

### Example: Using Recursive method

In the below example, a recursive function called factorial() is used to calculate factorial of a number.

def factorial(x):
if x == 0 or x ==1:
return 1
else:
return x*factorial(x-1)

print("10! = ", factorial(10))
print("6! = ", factorial(6))


Output

10! =  3628800
6! =  720


### Example: Using Iterative method

The factorial of a number can also be calculated using iterative method.

def factorial(x):
final = 1
for i in range(x,1,-1):
final = final * i
return final

print("10! = ", factorial(10))
print("6! = ", factorial(6))


Output

10! =  3628800
6! =  720


### Example: Using Short-hand If-else method (Ternary operator)

In the below example, the factorial of a number is calculated using short-hand if-else method.

def factorial(x):
y = 1 if (x == 0 or x ==1) else x * factorial(x-1)
return y

print("10! = ", factorial(10))
print("6! = ", factorial(6))


Output

10! =  3628800
6! =  720