using System;

public class Program

{

    public static void Main()

    {   var arr  = new int[] {1,2,3,4,5};

        var solution = new Solution();

​

        Console.WriteLine(solution.Rob(arr));

        Console.ReadLine();

    }

}

​

public class Solution {

    public int Rob(int[] nums) {

        var amountOdd = 0;

        for(var i = 0; i < nums.Length; i++) {

            if ( i % 2 != 0){

                amountOdd += nums[i];

            }

        }

        var amountEven = 0;

        for(var i = 0; i < nums.Length; i++) {

            if ( i % 2 == 0){

                amountEven += nums[i];

            }

        }

        return Math.Max(amountOdd, amountEven);

    }

}