using System;

namespace exercicios
{
	class Exercicio2{
		public static void Init()
		{
			int n;
			Console.WriteLine("Insert a value");
			n = int.Parse(Console.ReadLine());
			
			Console.WriteLine("{0}! = {1}",n,calcularFatorial(n));
			
		}
		static int calcularFatorial(int n)
		{
			int fat = 1;
			
			for(int i = 1; i <= n; i++)
			{
				fat *= i;
			}
			
			return fat;
		}
	}
}