To find factorial of a number in C++ Programming a common question in practical exams. Not only in C++, but also in C, Java, VB, C#, Python, etc.

What is factorial of a number?

Factorial of a number is the product of numbers from 1 to that number.

For example:

If we want to find factorial of 5,
Then it should be : 1 x 2 x 3 x 4 x 5 = 120.
Like this factorial of 4 should be 24. ( 1 x 2 x 3 x 4 = 24).
In computer, we use * symbol instead of multiplication symbol (x).

## C++ Program to find Factorial of a Number

Here we find factorial of a given number using for loop, which starts from 1 till to given number. Variable ‘fact’ gets multiplication products from 1 to that number.

```#include <iostream>
using namespace std;

int main()
{
int num, fact = 1;
cout << "Type a number : " ;
cin>>num;
for(int i=1;i<=num;i++)
{
fact = fact * i;
}
cout<<"Factorial of " << num << " is : "<< fact;
return 0;
}
```

### Using While Loop

```#include <iostream>
using namespace std;

int main()
{
int num, fact = 1, i=1;
cout << "Type a number : " ;
cin>> num;
while(i <= num)
{
fact = fact * i;
i++;
}
cout<< "Factorial of " << num << " is : "<< fact;
return 0;
}
```

## Find Factorial using Recursion

Recursion is the calling a function from it’s function body.
Here is a function named factorial and inside it’s body, program call again same function name(factorial) again.

```#include <iostream>
using namespace std;
int factorial(int);

int main()
{
int num;
cout << "Type a number : " ;
cin>>num;
cout<<"Factorial of " << num << " is : "<< factorial(num);
return 0;
}
int factorial(int num)
{
if(num == 1)
return 1;
else
{
return(num * factorial(num-1));
}

}

```

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