Work Note 11, DM819, fall 2011

Lecture November 18

• Segment Trees (section 10.3).

Exercises November 22

• Problems 2 and 4 from the Winter 1999/00 exam set.
• Solve the problem of finding the set of dominating points from Problem 2 above in O(n log n) using a divide-and-conquer strategy. Hint: consider the point with the largest y-value to the right of the x-median.
• Try to come up with a heuristic for computing convex hull faster in practice. The algorithms we have are O(n log n), but maybe one could use O(n) time to rule out a lot of points and then only run the convex hull algorithm on a much smaller set of point. Try to program the convex hull algorithm from Chapter 1 and your newly designed algorithm and time them on a very large number of uniformly distributed points.