Work Note 13, DM819, fall 2009

Discussion Section December 15

• Exercises 14.5, 14.12, 14.13, 14.14.
• In the balancing algorithm for quadtrees, which runs in O(dn), where n is the size of the tree, the O(d)-part is due to searches for neighbor nodes to check if they are more finely divided than the current node. Here, d denotes the height of the quadtree. Consider maintaining a constant amount of extra information in the internal nodes of a quadtree such that this information can be obtained in constant time, thereby reducing the time complexity of the balancing algorithm to O(n).

Discussion Section December 18

• Exercises 15.1, 15.3, 15.5.
• Evaluation.
• About the exam.