Find connected components in linked list
Last updated: September 27, 2025
Quick Overview
Given a linked list where each node may point to other nodes, identify and return all the connected components in the list. A connected component is defined as a subset of nodes such that there is a path between any two nodes in that subset. The output should be a list of lists, where each inner list contains the values of the nodes in a connected component.
TikTok
September 27, 20250
11
4,443 solved
Given a linked list where each node may point to other nodes, identify and return all the connected components in the list. A connected component is defined as a subset of nodes such that there is a path between any two nodes in that subset. The output should be a list of lists, where each inner list contains the values of the nodes in a connected component.
This coding problem is frequently asked during Onsite at TikTok. The interviewer is testing your ability to translate a problem into clean, working code while discussing time and space complexity. TikTok expects candidates to write production-quality code, not just solve the puzzle.
What the Interviewer Expects
- Quickly identify the optimal approach and its theoretical basis
- Handle complex algorithm design with multiple interacting components
- Write concise, elegant code under time pressure
- Prove correctness of your approach and discuss alternative solutions
- Optimize beyond the obvious: discuss constant factor improvements
- Address follow-up variations and explain how the solution generalizes
Key Topics to Cover
How to Approach This
- Clarify input constraints and edge cases before writing code.
- Walk through your approach verbally and confirm with the interviewer before coding.
- Start with a brute force solution, then optimize. Mention time and space complexity.
- Test your solution with examples, including edge cases like empty input or duplicates.
- Consider common patterns: sliding window, two pointers, hash map, BFS/DFS, dynamic programming.
Possible Follow-up Questions
- Can you solve this in a single pass?
- Can you optimize the space complexity of your solution?
- How would you parallelize this solution?
Sharpen Your Skills on Codemia
Practice similar problems with our interactive workspace, get AI feedback, and track your progress.
Practice DSA ProblemsSample Answer
Problem Analysis
To tackle the problem of finding connected components in a linked list, we can utilize the Depth-First Search (DFS) approach. Each node in the linked list can potentially point to another node, an...
Approach
- Initialization: Start by creating a set to keep track of visited nodes and a list to store the connected components.
- Traversal: For each node in the linked list, if it hasn't been visit...
Submit Your Answer
