Lesson overview · Free interview practice

Segment Trees

Efficiently perform range queries on arrays.

Topics in the full lesson
  • Concept and Use Cases
  • Key Concepts
  • Time and Space Complexity
  • Segment Tree Operations and Methods
  • Practical Tips and Tricks
  • Common Gotchas
  • Advanced Topics
  • Interview Tips and Tricks
  • Common Mistakes

Practice Problems

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CodingMedium

Range Sum Query - Mutable

Question

Implement NumArray supporting update(index, val) and sumRange(left, right) over a mutable array, each in O(log n) time.

Take a moment to think about this before revealing the answer

Explain your reasoning or try an implementation before comparing answers.

Practice on LeetCode
CodingHard

The Skyline Problem

Question

Given a list of buildings with their heights and starting and ending positions, determine the height of the skyline at each point in time, represented by an ordered pair of (x-coordinate, y-coordinate).

Take a moment to think about this before revealing the answer

Explain your reasoning or try an implementation before comparing answers.

Practice on LeetCode

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