Why are we subtracting minimum subarrray sum formed from cumullative sum why the pragraph is not clear
But we should keep in mind the fact that the maximum sum of the inverted subarray is actually
the minimum sum subarray for the original array. So if we subtract the negative value of this
new sum from the cumulative sum of the original array we will get another candidate for the
answer and name it candidate2. Then compare both the candidates and return the larger
number.