Factorial

C++ PROGRAMS

Factorial of any natural number is the product  of that number and all the natural numbers less than that. It is indicated with the help of the sign: ! . 

For example:

4!= 4 X 3 X 2 X 1 = 24

8!= 8 X 7 X 6 X 5 X 4 X 3 X 2 X 1 = 40320

Note: 0! = 1

In the following program the user enters any natural number and the output is the factorial of that number.

In this I will use for-loop.

Code:

#include<iostream.h>

#include<conio.h>

void main()

{

clrscr();

long a,i,fact=1;

cout<<"Factorial"<<"\n";

cout<<"Enter any natural number: ";

cin>>a;

for(i=1;i<=a;i++)

{

 fact=fact*i;

}

cout<<"Ans. "<<fact;

getch();

}

Output: 

First Run:

Second Run:

Note: if you enter a number more than 10, then sometimes the output may be a junk value(random value). This is because the factorials of those numbers are very large.

For any queries or suggestions please comment !