Tobsan

import java.util.Scanner;

public class Test
{
     public static void main(String [] args)
     {
         Scanner scan = new Scanner(System.in);
         int x = scan.nextInt();
         int fac = 1;
         for(int i=x;i>0;i--)
         {
             fac = fac * i;
         }
     }
}