using System;

public class Program

{

    public static int MaxSubarraySum(int[] ay){

        int compareItem=0,maxItem=0;

        int n= ay.Length;

        for(int i=0; i<n; i++){

            maxItem= maxItem + ay[i];

            compareItem = ay[i];

            if(compareItem < maxItem){

                compareItem= maxItem;

            }

            else if(compareItem < 0){

                compareItem= 0;

            }

        }

        return maxItem;

    }

    public static void Main()

    {

        int[] nums = {-2, 1, -3, 4, -1, 2, 1, -5, 4};

        //int[] nums = { 4, -1, 2, 1};

        int maxSum =MaxSubarraySum(nums); 

        Console.WriteLine(maxSum);

    }

}