Advanced~3h
Backtracking in Data Structures & AlgorithmsInterview Readiness Check
Build solutions incrementally, prune when impossible — permutations, subsets, N-queens, Sudoku.
permutationssubsetscombinationsN-queensSudokuDFS prune
Learning path
Try a sample question
Generate all permutations of [1, 2, 3]. Which algorithmic pattern systematically explores all orderings?
A.Iterative loops — nest one loop per position
B.BFS — use a queue to build permutations level by level
C.Backtracking — at each position, try each unused number, recurse to fill remaining positions, then undo the choice (backtrack) to try the next option
D.Dynamic programming — build permutations from smaller ones
Sign up free to take the full check and see the answer with an explanation.
What this module tests
- Conceptual understanding of backtracking fundamentals
- Trade-offs and design decisions in real system scenarios
- permutations and subsets — applied knowledge
- Interview-style reasoning and explanation quality
Free to start
Take the Backtracking check →
10 questions · Dimension scoring · AI coach feedback · Shareable result
Test your knowledge — free →No credit card · Takes 10–15 min
Frequently asked questions
- What does the Backtracking check test?
- The check covers build solutions incrementally, prune when impossible — permutations, subsets, n-queens, sudoku. Questions span beginner to advanced difficulty and test both conceptual understanding and practical trade-off reasoning.
- What keywords should I know for Backtracking?
- Key concepts include: permutations, subsets, combinations, N-queens, Sudoku, DFS prune. These frequently appear in data structures & algorithms interviews at product and infrastructure companies.
- How many questions are in the check?
- Each check has 10 questions — a mix of MCQ and short-answer. You get scored by dimension (e.g., scalability, consistency) so you know exactly where to focus.
- How long does it take to study Backtracking?
- Most engineers spend around 3 hours on this module. The check itself takes about 10–15 minutes. You can retake it up to 3 times per day.
- What prerequisite knowledge do I need before Backtracking?
- Backtracking builds on Trees: DFS & Recursion. Complete those first for the best results.
- Is permutations, subsets, combinations covered?
- Yes. The Backtracking module covers permutations, subsets, combinations among other key concepts. The check includes questions that reflect real data structures & algorithms interview patterns.