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LetsGit.IT/Categories/Algorithms
Algorithmsmedium

Kruskal vs Prim: what is the main difference and typical data structures?

Tags
#mst#kruskal#prim#union-find#priority-queue
Back to categoryPractice quiz

Answer

Kruskal builds the MST by sorting edges and adding them if they don’t create a cycle (usually with DSU/Union‑Find). Prim grows the MST from a start node using a priority queue of edges. Kruskal is often good for sparse graphs; Prim is convenient when you have adjacency lists.

Advanced answer

Deep dive

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

  • Context (tags): mst, kruskal, prim, union-find, priority-queue
  • 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 "kruskal-vs-prim:-what-is-the-main-difference-and"
function explain() {
  // Start from the core idea:
  // Kruskal builds the MST by sorting edges and adding them if they don’t create a cycle (usua
}

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

Algorithms
Kruskal vs Prim for MST — how do they differ?
#mst#kruskal#prim
Data Structures
Binary heap vs binary search tree: which operations are efficient?
#heap#bst#priority-queue
Data Structures
What operations does a priority queue support and how is it typically implemented?
#priority-queue#heap
  • How would you test edge cases?
  • #ordering
    Data Structures
    What is the heap property in a binary heap?
    #heap#binary-heap#priority-queue
    Data Structures
    What problem does Union-Find (Disjoint Set Union) solve?
    #union-find#dsu#kruskal