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LetsGit.IT/Categories/Data Structures
Data Structureshard

What is a suffix array (or suffix tree) used for?

Tags
#strings#suffix-array#suffix-tree#pattern-matching
Back to categoryPractice quiz

Answer

They are string data structures used for fast substring and pattern queries (e.g., “does pattern P appear in text T?”). They enable efficient searches and are used in text indexing, search, and bioinformatics.

Advanced answer

Deep dive

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

  • Context (tags): strings, suffix-array, suffix-tree, pattern-matching
  • 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-is-a-suffix-array-(or-suffix-tree)-used-for"
function explain() {
  // Start from the core idea:
  // They are string data structures used for fast substring and pattern queries (e.g., “does p
}

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
What is a trie and why is it good for prefix search/autocomplete?
#trie#prefix#autocomplete
Algorithms
KMP string search: how does the LPS/prefix table avoid re-checking characters?
#kmp#string#pattern-matching
Algorithms
KMP vs naive substring search — what’s the core idea of KMP?
#kmp#string-search
  • How would you test edge cases?
  • #pattern-matching