FibonacciRecursionMemoization

using System;
using System.Linq;
using System.Collections.Generic;

namespace Fibonacci
{
    class Program
    {
        static int[] numbers;

        static int Fib(int n)
        {
            if (numbers[n] != 0)
            {
                return numbers[n];
            }

            if (n == 1 || n == 2)
            {
                return 1;
            }

            var result = Fib(n - 1) + Fib(n - 2);

            numbers[n] = result;

            return result;
        }

        static void Main()
        {
            int n = int.Parse(Console.ReadLine());
            numbers = new int[n + 1];
            int result = Fib(n);
            Console.WriteLine(result);
        }
    }
}