(Closest pair of points) Section 22.8 introduced the following algorithm for finding the closest pair of points using a divide-and-conquer approach: Step 1: Sort the points in increasing order of x-coordinates. For the points with the same x-coordinates, sort on y-coordinates. The result should be a sorted collection of points denoted by S. Step 2: Divide S into two subsets, S1 and S2, of equal size about the midpoint of the sorted list S. Include the midpoint in S1. Recursively find the closest pair in S1 and S2. Let d1 and d2 denote the distance of closest pairs in the two subsets, respectively. Step 3: Find the closest pair between a point in S1 and a point in S2 and denote the distance between them as d3. The closest pair is the one with distance equal to the minimum of {d1, d2, d3}. The Algorithm for Obtaining stripL and stripR is: for each point p in pointsOrderedOnY if (p is in S1 and mid.x - p.x <= d) append p to stripL; else if (p is in S2 and p.x - mid.x <= d) append p to stripR; Algorithm for Finding the Closest Pair in Step 3 d =