Lecture 28

Learning objectives

After this class, you should be able to:

1. Define a heap.
2. Given a sequence of insertions into a min heap, draw the resulting heap.
3. Given a heap drawn as a tree, show its array representation.
4. Given the array representation of a heap, draw it as a tree.
5. Give the time complexity for insertion into a heap.
6. Determine the children and parent of a node, given its index in its array representation.
7. Give applications of heaps.
8. Explain why data structures that we have studied earlier are not ideal for implementing a priority queue.

Reading assignment

1. Section 6, up to section 6.3.3.
2. Lecture: Priority queues.

Exercises and review questions

• Exercises and review questions on current lecture's material
  1. Draw the pointer representation of a max heap whose array representation is as follows: 16 14 10 8 7 9 3 2 4 1.
  2. Show the heap that results from inserting 11 into the heap above.
  3. Prove that the children of node i are 2i+1 and 2i+2, where the root is node 0.

• Questions on next lecture's material
  1. None.

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Last modified: 4 Nov 2013