Consider the following function, which given an integer n, computes the sum of the first n^2 elements of the arithmetic progression:
int sumThroughSquare(int n) {
int sum = 0;
for (int i = 1; i <= n*n; i++) {
sum += i;
}
return sum;
}
What is the tightest bound you can provide for the asymptotic growth rate of the running time, if we use n as the measure of the problem size? (3 pts: 2 for correctness of the bound + 1 for tightness of the bound).