(C++) Write an O(n² log n) algorithm; assuming you have (i) function int [] sort(int A[]) returning a sorted array B with O(n log n) complexity (ii) memory for an auxiliary array int pairSums[] to store sum of all possible pairs (a[i], a[j]). Justify your complexity and what would be your memory complexity in big-O notation.

int fourSumOn2log(int A[], int length) {