#include <iostream>
#include <cstdlib>

using namespace std;

int main(void)
{
   int n;
   cout << "dar el numero del que se quiere calcular factorial\n";
   cin >> n;

   int k;
   k= 1;
   int prod;
   prod= 1;
   while (k<=n)
      {
       prod= prod*k; 
       k= k+1;
      }
   cout << "factorial = " << prod << endl;
   return EXIT_SUCCESS;
}