using System;

public class Program

{

    public static void Main()

    {

        int[] input = { 100, 200, 50, 60};

        var differences = CalculateDifferences(input);

​

        int tempResult = 0;

        int result = 0;

        for(int i = 0 ; i< differences.Length; ++i)

        {       

            tempResult = tempResult >= 0? tempResult += differences[i]: 0;

            if (result < tempResult)

            {

                result = tempResult;

            }

        }

​

        Console.WriteLine(result);

    }

    private static int[] CalculateDifferences(int[] input)

    {

        int[] result = new int[input.Length-1];

        for(int i =1; i< input.Length; ++i)

        {

            result[i-1] = input[i] - input[i-1];

        }

        return result;

    }

}