import cs1.Keyboard;
/**
   Calculate the factorial of an integer n.
   @author Greg Vogl
   last modified 2003-09-22
*/
public class Factorial
{
   /**
      Calculate the factorial of an integer n.
   */
   public static void main (String[] args)
   {
      System.out.println("Calculate the factorial of an integer n.");

      // get input
      System.out.println("Type an integer and press Enter.");
      int n = Keyboard.readInt();

      // calculate statistics
      long factorial = 1;
      for (int i=1; i<=n; i++)
         factorial *= i;

      // output results
      System.out.println("The factorial of "+ n + " is " + factorial + ".");
   }
}