Recursions

using java.util;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SoftSvetlina
{
    class Program
    {
        static int Factorial(int n)
        {
            if (n == 0)
            {
                return 1;
            }
            return Factorial(n - 1) * n;
        }

        static void CountDown(int start)
        {
            if (start == -10)
            {
                return;
            }
            Console.WriteLine(start);
            CountDown(start - 1);
        }

        static int fib(int n)
        {
            if (n == 0)
            {
                return 0;
            }
            else if (n == 1)
            {
                return 1;
            }
            return fib(n - 1) + fib(n - 2);
        }
        static void Main()
        {
            Console.WriteLine(fib(12));
        }
    }
}