/*
	The program uses recursive to find the factorial
	
*
*/

import java.util.*;

public class Factorial
{
	public static void main(String[] args)
	{
	
		Scanner key = new Scanner(System.in);
		
		int number;
		
		// Gets the number from the user
		
		System.out.println("Enter a nonnegative integer: ");
		number = key.nextInt();
		
		/*
			Pass number into factorial method
			outputs the factorial
			
		*
		*/
		
		System.out.println(number + "!" + " is " + factorial(number));
		
	}
	
	// Recursive method
	
	private static int factorial(int n)
	{
		// Base class
		
		if(n==0)
		{
			return 1;
		}
		
		else
			return n*factorial(n-1);
	}
}