Rounds

Coding & DSA Round

60-minute algorithmic problem-solving assessment with 4-tier scorecard

Round Structure (60 min)

TimePhasePurpose
0-5 minWarm-upIntroduce yourself, set expectations
5-10 minProblem StatementPresent problem, candidate asks clarifying questions
10-40 minImplementationCandidate codes solution, discusses approach
40-50 minTesting & OptimizationWalk through test cases, discuss improvements
50-60 minFollow-upsExtensions, edge cases, complexity analysis

4-Tier Scorecard

Dimension1 Strong No-Hire2 No-Hire3 Lean Hire4 Strong Hire
Algorithmic Thinking Cannot identify problem type Identifies pattern but fails to implement Correct approach with minor bugs Optimal approach, clean implementation
Complexity Analysis Cannot state Big-O States Big-O but incorrect Correct Big-O, cannot optimize Analyzes multiple approaches, picks optimal
Edge Cases Ignores edge cases entirely Handles 1-2 when prompted Identifies most independently Exhaustive coverage; adversarial inputs
Code Quality Unreadable; no structure Functional but messy Clean, modular; reasonable naming Production-ready; self-documenting
Communication Cannot explain thinking Explains only when asked Thinks aloud; structured Drives discussion; explores alternatives
Testing Cannot verify own code Traces one example when prompted Tests happy path + edge cases Writes formal tests; discusses strategy

Level Expectations

LevelExpected Performance
SDE 1Solves Easy in <15min, Medium with hints
SDE 2Solves Medium cleanly in <25min
SDE 3Solves Medium in <20min, attempts Hard optimally
SDE 4Solves Hard, discusses multiple approaches and trade-offs

Sample Problems by Category

Arrays & Hashing

  • Two Sum O(n) hash map approach
  • Merge Intervals sort + merge
  • Product of Array Except Self prefix/suffix

Trees & Graphs

  • Lowest Common Ancestor recursive DFS
  • Course Schedule topological sort
  • Serialize/Deserialize Binary Tree

Dynamic Programming

  • Longest Increasing Subsequence O(n log n)
  • Coin Change bottom-up tabulation
  • Edit Distance 2D DP

Heaps & Stacks

  • Merge K Sorted Lists min-heap
  • LRU Cache DLL + HashMap
  • Min Stack auxiliary stack

📖 Full question bank: See the DSA Problems page for 25 complete solutions with complexities and follow-ups.