# Factorial Example Program Using Function In C Programming Language

### Definition of Factorial

In mathematics, the factorial of a non-negative integer n, denoted by n!, is the product of all positive integers less than or equal to n.

For example,

``6! = 6 x 5 x 4 x 3 x 2 x 1 = 720``

The value of 0! is 1, according to the convention for an empty product.

### Example Program For Factorial In C Programming Language

``````/*  Example Program For Find Factorial Number In C Programming Language
little drops @ thiyagaraaj.com
Coded By:THIYAGARAAJ MP             */

#include<stdio.h>
#include<conio.h>

// define Function and Its Argument Type
long factorial(long);

//Main Function
int main()
{
// Variable Declaration for Factorial Function Input
long f;

printf("Enter the Number for Factorial Calculation :?);
scanf("%ld",&f);
//factorial calculation
printf("The Factorial of %ld is %ld",f,factorial(f));

// Wait For Output Screen
getch();
//Main Function return Statement
return 0;
}

// factorial Function
long factorial(long n)
{
int counter;
long fact = 1;

//for Loop for Factorial Calculation Block
for (counter = 1; counter <= n; counter++)
{
fact = fact * counter;
}
return fact;
}
``````

### Sample Output

``````Enter the Number :6

6 Factorial Value Is 720``````