Calculate the theoretical time complexity by counting the number of subtractions as basic operation. What do you think is the Big-Oh for the complexity? Prove how did you get the big-Oh.

NegativeSubSum = 0;

for (i = 1; i <= 2*n; i++) //10

for (j = 1; j <= i+1; j++)//

NegativeSubSum = NegativeSubSum j + 1;