Here you will get python program to find factorial of number using for and while loop.

Factorial of a number is calculated by multiplying it with all the numbers below it starting from 1.

For example factorial of 4 is 24 (1 x 2 x 3 x 4).

Below program takes a number from user as an input and find its factorial.

## Python Program to Find Factorial of Number

### Using For Loop

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num = int(input("enter a number: ")) fac = 1 for i in range(1, num + 1): fac = fac * i print("factorial of ", num, " is ", fac) |

**Output**

*enter a number: 5*

*factorial of 5 is 120*

### Using While Loop

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num = int(input("enter a number: ")) fac = 1 i = 1 while i <= num: fac = fac * i i = i + 1 print("factorial of ", num, " is ", fac) |

**Output**

*enter a number: 4*

*factorial of 4 is 24*

### Video Tutorial

Comment below if you have any queries related to above python factorial program.

why num+1 in for loop ?

Because range(start, end) function will generate numbers from start and end-1. In above program we want to generate numbers from 1 to num, I have used num+1 that means (num+1)-1 which ultimately means num.

As we know that if we write only num,it will take range (1,num-1)means if we write only num it will range from 1 to num -1. And if we range (1,num+1)it range the number also that you have entered.

**THAT’S THE SOLUTION**

Because if you give only num it will end with 1 less number

Eg.for i in range(1,5)

Print(i)

1

2

3

4

It will olny print 4 number there fore we add num+1

def factorial(a):

result=1

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

result= result*i

return result

a = input(‘ur number please ‘)

y = (factorial(a))

print(y + str (‘is ur answer’))

can any body tell me where is the problem

indentation problem

result must be under the loop.

press tab button on reach lines from result

You first define function and then you didn’t use it . So off course no output. Example :- factorial(4)

Hi

i’m Sven Brodowski

my english is not verry good

youre programms are super

I’m learning Python and Java

my Questions

have you got a programm in Python

where can do inverse Matrix

I live in heilbronn germanny

ok see you later

Hello!

I have read my book from Codio and have attempted the challenge. Here is what I have coded:

# Get N from the command line

import sys

N = int(sys.argv[1])

# Your code goes here

N!=N*(N-1)*(N-2)*(N-3)*(N-4)*1

print (N)

It is telling me my output is 4.

I am confused, because if N is 4 based upon what the user input, why is it not completing the calculation?

Can you help?

import math

x = math.factorial(2)

print(x)

An integer t, 1<=t<=100, denoting the number of testcases, followed by t lines, each containing a single integer n, 1<=n<=100.

Output

For each integer n given at input, display a line with the value of n!

Find the factorial!!

python program on factorial using recurssion?

def factorial(a):

if a == 0 or a ==1:

return a

else:

return a * factorial(a-1)

a = int(input())

y = factorial(a)

print( y)

With the for loop, how would I be able to have it display the actual calculation along with the answer, for example if user enters 4, I need it to display:

4! = 1 x 2 x 3 x 4 = 24

I am able to get the code to display the answer, however not the actual equation.

Thanks for your help in advance!

Thank you! This was very helpful.

how to find if factorial is even or odd

num = int(input(“enter a number: “))

fac = 1

for i in range(1, num):

fac = fac *num

num = num-1

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