##### Find number of indices i such that a[i] < x.

You are given an array a containing n distinct integers. You are also given multiple integers xi. For each xi, you need to ﬁnd number of indices i such that a[i] < x. You are allowed to do pre-computation of O(nlogn), but for each i, you should be able to answer in O(logn). You are not allowed to use sorting.