C Program: Find out the Factorial of a Number by using While Statement

Factorial :

• Factorial of a non Negative number n is denoted by n!
• Factorial Formula:  n! = 1*2*3*4.................*n
•  Example:  5! = 5*4*3*2*1

Statement of C program: Input a number and compute its Factorial:

#include<stdio.h>

#include<conio.h>

void main()

{

int a,b,c ;

clrscr();

printf("Enter the value of a\n ");

scanf("%d" ,&a);

b=1;

c=1;

while( b<=a )

{

c=c*b;

b++;

}

printf("Factorial=%d\n" , c)

getch();

}

Output1:

Enter the value of a

5 

Factorial=120

Output2:

Enter the value of a

7

Factorial=5040