**Write a program to calculate factorial of an entered number using for, while, do while, i. ****for loop,**

More examples on factorial,

C++ Program for Factorial using For, While & Do While

C Program to Calculate the Factorial using Function.

C Program to Calculate the Factorial using Recursion.

**Source Code:**

#include<iostream.h>

#include<conio.h>

void main()

{

int num,a,factorial=1;

cout<<“Enter number to find its Factorial:”;

cin>>num;

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

{

factorial=factorial*a;

}

cout<<“The Factorial of”<<num<<“=”<<factorial<<endl;

getch();

}

**Output:**

Enter number to find its Factorial:5

The Factorial of5=120

**ii.**

**do while loop**

**Source Code:**

#include<iostream.h>

#include<conio.h>

void main()

{

int num, i, factorial=1;

do

{

cout<<“Enter the number:”<<endl;

cin>>num;

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

factorial*=i;

cout<<“Factorial of”<<num<<“is:”<<factorial;

}

while(num<=2 && num>=30);

system(“Pause”);

getch();

}

**Output:**

Enter the number:

5

Factorial of5is:120

Press any key to continue . . .

**iii.**

**while loop.**

**Source Code:**

#include<iostream.h>

#include<conio.h>

void main()

{

clrscr();

int no,fact=1,i;

cout<<“Enter the no.”<<endl;

cin>>no;

i=1;

while(i<=no)

{

fact=fact*i;

i++;

}

cout<<“The factorial is “<<fact;

getch();

}

**Output:**

Enter the no.

5

The factorial is 120