Program For Factorial of a Number

Generally factorial of a number of a non-negative integer is the multiplication of all integers smaller than or equal to n. For example, Factorial of 6 is 6*5*4*3*2*1 which is 720.

Recursive Solution:

Factorial can be calculated by following recursive formula.

  n! = n * (n-1)!
  n! = 1 if n = 0 or n = 1

C++ program to find factorial of a given no.

// C++ program to find factorial of given number
#include <iostream>
using namespace std;

// function to find factorial of given number
unsigned int factorial(unsigned int n)
{
	if (n == 0)
		return 1;
	return n * factorial(n - 1);
}

// Driver code
int main()
{
	int num = 5;
	cout << "Factorial of "
		<< num << " is " << factorial(num) << endl;
	return 0;
}

// This code is contributed by Shivi_Aggarwal

C program to find factorial of a given no.

// C program to find factorial of given number
#include <stdio.h>

// function to find factorial of given number
unsigned int factorial(unsigned int n)
{
	if (n == 0)
		return 1;
	return n * factorial(n - 1);
}

int main()
{
	int num = 5;
	printf("Factorial of %d is %d", num, factorial(num));
	return 0;
}

Java program to find factorial of a given no.

// Java program to find factorial of given number
class Test {
	// method to find factorial of given number
	static int factorial(int n)
	{
		if (n == 0)
			return 1;

		return n * factorial(n - 1);
	}

	// Driver method
	public static void main(String[] args)
	{
		int num = 5;
		System.out.println(
			"Factorial of " + num
			+ " is " + factorial(5));
	}
}

Python program to find factorial of a given no.

# Python 3 program to find
# factorial of given number

# Function to find factorial of given number
def factorial(n):
	
	if n == 0:
		return 1
	
	return n * factorial(n-1)

# Driver Code
num = 5;
print("Factorial of", num, "is",
factorial(num))

# This code is contributed by Smitha Dinesh Semwal

C# program to find factorial of a given no.

// C# program to find factorial
// of given number
using System;

class Test {
	// method to find factorial
	// of given number
	static int factorial(int n)
	{
		if (n == 0)
			return 1;

		return n * factorial(n - 1);
	}

	// Driver method
	public static void Main()
	{
		int num = 5;
		Console.WriteLine("Factorial of "
						+ num + " is " + factorial(5));
	}
}

// This code is contributed by vt_m

PHP program to find factorial of a given no.

<?php
// PHP program to find factorial
// of given number

// function to find factorial
// of given number
function factorial($n)
{
	if ($n == 0)
		return 1;
	return $n * factorial($n - 1);
}

	// Driver Code
	$num = 5;
	echo "Factorial of ", $num, " is ", factorial($num);

// This code is contributed by m_kit
?>

Output: