C# Program to Calculate Factorial of a Number Using Recursion

This program takes a positive integer from user and calculates the factorial of that number. Suppose, user enters 6 then,

Factorial will be equal to 1*2*3*4*5*6 = 720

You’ll learn to find the factorial of a number using a recursive function in this example.

Visit this page to learn, how you can use loops to calculate factorial.

Source Code:

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace simpleCalc

{

class Program

{

static void Main(string[] args)

{

Console.WriteLine("\nRecursion : Find the factorial of a given number :");

Console.WriteLine("-------------------------------------------------------");

Console.Write(" Input any positive number : ");

int n1 = Convert.ToInt32(Console.ReadLine());

long fact = FactCalc(n1);

Console.WriteLine(" The factorial of {0} is : {1} ", n1, fact);

Console.ReadKey();

}

private static long FactCalc(int n1)

{

if (n1 == 0)

{

return 1;

}

return n1 * FactCalc(n1 - 1);

}

Output: