midSorting

Merge Sort vs Quick Sort: When to use which?

Updated Apr 28, 2026

Short answer

Merge Sort is stable and better for linked lists; Quick Sort is in-place and generally faster for arrays.

Deep explanation

Intermediate sorting algorithms focus on O(n log n) efficiency and specialized constraints. Merge Sort is stable and better for linked lists; Quick Sort is in-place and generally faster for arrays.

Real-world example

Standard library sort implementations (e.g., Python's Timsort).

Common mistakes

  • Forgetting that Merge Sort requires O(n) extra space.

Follow-up questions

  • Is Quick Sort stable?
  • Time complexity of Heap Sort?

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