import java.util.Scanner;

public class Factorial_Recursive
{
	public static int calculateFactorial(int num)
	{

		int result;
		
		if(num==1)
			result=1;
		else
			result = num * calculateFactorial(num-1);
		
		return result;
	}
	
	public static void main(String[] args)
	{
		Scanner scan = new Scanner(System.in);
		System.out.print("Enter a number: ");
		int n= scan.nextInt();
		
		int res = calculateFactorial(n);
		
		System.out.println( n + "! = " + res);
	}
}