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LetsGit.IT/Categories/Data Structures
Data Structureshard

What are Balanced Trees (e.g., AVL, Red-Black)?

Tags
#tree#binary-search-tree#balancing#algorithm
Back to categoryPractice quiz

Answer

Balanced trees such as AVL or Red‑Black are self‑balancing binary search trees that keep height proportional to log n by performing rotations after inserts and deletes. This guarantees search/insert/delete in O(log n) even in the worst case.

Advanced answer

Deep dive

Expanding on the short answer — what usually matters in practice:

  • Context (tags): tree, binary-search-tree, balancing, algorithm
  • Complexity: compare typical operations (average vs worst-case).
  • Invariants: what must always hold for correctness.
  • When the choice is wrong: production symptoms (latency, GC, cache misses).
  • Explain the "why", not just the "what" (intuition + consequences).
  • Trade-offs: what you gain/lose (time, memory, complexity, risk).
  • Edge cases: empty inputs, large inputs, invalid inputs, concurrency.

Examples

A tiny example (an explanation template):

// Example: discuss trade-offs for "what-are-balanced-trees-(e.g.,-avl,-red-black)?"
function explain() {
  // Start from the core idea:
  // Self-balancing binary search trees that maintain a height of O(log n), ensuring efficient 
}

Common pitfalls

  • Too generic: no concrete trade-offs or examples.
  • Mixing average-case and worst-case (e.g., complexity).
  • Ignoring constraints: memory, concurrency, network/disk costs.

Interview follow-ups

  • When would you choose an alternative and why?
  • What production issues show up and how do you diagnose them?

Related questions

Data Structures
AVL vs Red-Black tree — what’s the trade-off?
#avl#red-black#balancing
Algorithms
What does it mean that a sort is stable, and why does it matter?
#sorting#stable-sort#algorithm
Algorithms
What is Dijkstra's Algorithm?
  • How would you test edge cases?
  • #graph
    #shortest-path
    #dijkstra
    Algorithms
    Explain Binary Search.
    #search#binary-search#algorithm