Heeeello!

I'm trying to find a way how to compute a factorial of any given number.

the factorial of a positive integer is defined as follows:

n! = n(n-1)(n-2)(n-3).....

what I'm trying to do here is to find a way so that the program will know how many steps it need to do to get to (1).

example) I want to compute the factorial of the number 6.

6! = 6(5)(4)(3)(2)(1) = 720

I was just trying something like:

Code:
#include <iostream>
using namespace std;

int main()
{
        int n = 0;
	int n1;
	cout << "enter a positive integer and the compute the factorial of: ";
	cin >> n;
	n1 = n(n-1)(n-2)(n-3);
	cout << n1;
	_getch();
	return 0;
}
ofc, this will not work but.. yeah, a little help please ^^