Hash Tables, Heaps, and Priority Structures · Sorting

Heap Sort

Heap sort uses heap structure to repeatedly select the next largest or smallest item with predictable O(n log n) behavior.

Student Focus

We use heap sort to reinforce why data structure invariants can drive algorithm design.

Guided Lesson Notes

How Code Scholars teaches Heap Sort

This guide helps students understand the idea, implement it carefully, explain the runtime, and recognize when the pattern belongs in a larger problem.

In a session, students usually start with a small trace, then write or review code, then test edge cases. The final step is a short explanation: what the structure or algorithm stores, why it is correct, and what changes when the input grows.

Key Ideas

  • Heapify
  • Repeated removal
  • In-place sorting tradeoffs

Practice Prompts

  • Trace heap sort on a six-element array.
  • Compare heap sort with merge sort and quicksort.

Tutoring Connection

Turn the topic into usable problem-solving skill

Students can use this page before a lesson, after a difficult homework assignment, or while preparing for AP Computer Science A extensions, Advanced Topics in CS, USACO growth, or a college data structures course.