Advanced~3h
Graph Algorithms in Data Structures & AlgorithmsInterview Readiness Check
DFS/BFS on adjacency structures — islands, connected components, shortest path (unweighted).
adjacency listvisitedBFS shortestDFS componentsislandscycle detection
Learning path
Trees: BFS & Level OrderTrees: DFS & Recursion→Graph Algorithms ← you are here→Union Find / DSUTopological Sort
Try a sample question
Count the number of connected components (islands) in a grid of 0s and 1s. Each '1' connected to adjacent '1's (up/down/left/right) forms one island. Which traversal correctly counts every island exactly once?
A.For each unvisited '1' cell, run a DFS or BFS flood fill that marks every reachable '1' visited; each such launch corresponds to exactly one island.
B.Sort cells by value, then scan for transitions from 0 to 1
C.Scan the grid and count total '1' cells — every '1' represents a distinct island in a boolean grid
D.Run DFS from cell (0,0) once — a single traversal will find all islands regardless of separation
Sign up free to take the full check and see the answer with an explanation.
What this module tests
- Conceptual understanding of graph algorithms fundamentals
- Trade-offs and design decisions in real system scenarios
- adjacency list and visited — applied knowledge
- Interview-style reasoning and explanation quality
Free to start
Take the Graph Algorithms 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 Graph Algorithms check test?
- The check covers dfs/bfs on adjacency structures — islands, connected components, shortest path (unweighted). Questions span beginner to advanced difficulty and test both conceptual understanding and practical trade-off reasoning.
- What keywords should I know for Graph Algorithms?
- Key concepts include: adjacency list, visited, BFS shortest, DFS components, islands, cycle detection. 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 Graph Algorithms?
- 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 Graph Algorithms?
- Graph Algorithms builds on Trees: BFS & Level Order and Trees: DFS & Recursion. Complete those first for the best results.
- Is adjacency list, visited, BFS shortest covered?
- Yes. The Graph Algorithms module covers adjacency list, visited, BFS shortest among other key concepts. The check includes questions that reflect real data structures & algorithms interview patterns.