using System;

public class Program

{

    public static int GetCount(int n)

    {

        int Max = 32;

        if (n > Max) return -1;

        int[] arr = new int[Max];

        arr[1] = 2;

        arr[2] = 4;

        for (int i = 3; i <= n; i++)

        {

            arr[i] = arr[i - 1] + arr[i - 2];

        }

        return arr[n];

    }

    public static void Main()

    {

        Console.WriteLine("UniLecs");

        Console.WriteLine(string.Format("Answer = {0}", GetCount(13))); // 6

    }

}