C Program To Find Factorial Of A Number Using While Loop

In this c program, we are going to calculate the factorial of any entered number using while loop and for loop. We can also define a function to do so.

Calculate Factorial Of A Number Using While Loop

#include<stdio.h>
#include<conio.h>
void main()
{
 int num,i;
 long fact=1;
 clrscr();

 printf("\n Enter Any Number: ");
 scanf("%d",&num);

 if(num<=0)
 printf("\n Invalid Number! ");

 else
 {
   fact=num;

   i=1;
   while(i<num)
    {
      fact=fact*i;
      i++;
    }

    printf("\n Factorial = %ld",fact);
 }
 getch();

}

Output:

C Program To Find Factorial Of A Number Using For Loop

#include<stdio.h>
#include<conio.h>
void main()
{
 int num,i;
 long fact=1;
 clrscr();

 printf("\n Enter Any Number: ");
 scanf("%d",&num);
 if(num<=0)
 printf("\n Invalid Number ! ");

 else
 {
  fact=num;

  for(i=1;i<num;i++)
    {
     fact=fact*i;
    }

    printf("\n Factorial = %ld",fact);
 }
 getch();

}

I found the appropriate explanation of the above program in the video below. 

Find Factorial Of A Number Using Function

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

void factorial();

void main()
{
 clrscr();

 factorial();

 getch();

}

void factorial()
{
 int i,n;
 long fact=1;

 printf("\n Enter Any Number: ");
 scanf("%d",&n);

 if(n<=0)
 printf("\n Negative Number or Zero Not Allowed ! ");

 else
 {
  fact=n;

  for(i=1;i<n;i++)
    {
     fact=fact*i;
    }
 }
 printf("\n Factorial = %ld",fact);

 }

In this way, we can find factorial of any given number with the help of while loop, for loop as well as function.