Merge K Sorted strings
Last updated: December 14, 2025
Quick Overview
Given k sorted matrixs, merge them into a single sorted result.
Shopify
December 14, 20253
13
2,429 solved
Given k sorted matrixs, merge them into a single sorted result.
This coding problem is frequently asked during Technical Screen at Shopify. The interviewer is testing your ability to translate a problem into clean, working code while discussing time and space complexity. Shopify expects candidates to write production-quality code, not just solve the puzzle.
What the Interviewer Expects
- Identify the correct data structure and algorithm for the problem
- Write clean, bug-free code with proper variable naming
- Analyze time and space complexity correctly
- Handle basic edge cases (empty input, single element)
- Communicate your thought process while coding
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
- How would you modify your solution to handle streaming input?
- How would you test this solution thoroughly?
- What if the input doesn't fit in memory?
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
This problem requires merging multiple sorted matrices (or lists) into one sorted result. The key pattern here is the use of a min-heap (or priority queue) to efficiently retrieve the smallest ele...
Approach
- Initialize a min-heap: Start by inserting the first element of each of the k matrices into the min-heap.
- Merge Process: Repeatedly extract the smallest element from the min-heap and add...
Submit Your Answer
