using System;

public class Program

{

    /*

    Definition

    The Fibonacci numbers may be defined by the recurrence relation where

    F0 = 0, F1 = 1

    and

    Fn = Fn-1 + Fn-2

    sameple result

    +----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+-----+------+------+------+------+

    | F0 | F1 | F2 | F3 | F4 | F5 | F6 | F7 | F8 | F9 | F10 | F11 | F12 | F13 | F14 | F15 | F16 |  F17 |  F18 |  F19 |  F20 |

    +----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+-----+------+------+------+------+

    |  0 |  1 |  1 |  2 |  3 |  5 |  8 | 13 | 21 | 34 |  55 |  89 | 144 | 233 | 377 | 610 | 987 | 1597 | 2584 | 4181 | 6765 |

    +----+----+----+----+----+----+----+----+----+----+-----+-----+-----+-----+-----+-----+-----+------+------+------+------+

    */

    static int Fib(int n){

        // write your code here

        throw new NotImplementedException();

    }

    public static void Main()

    {

        var result = Fib(50);

        Console.WriteLine(result);

    }

}