In this program, You will learn how to find factorial of a number using the function in C++.

`3! = 1 * 2 * 3 => 6`

## Example: How to find factorial of a number using the function in C++.

```
#include<iostream>
using namespace std;
int factorial(int a) {
int i, f = 1;
for (i = 1; i <= a; i++) {
f = f * i;
}
return f;
}
int main() {
int a, f;
cout << "Enter a number:";
cin>>a;
f = factorial(a);
cout << "Factorial is:" << f;
return 0;
}
```

#### Output:

```
Enter a number:3
Factorial is:6
```