Find minimum cost in interval list
Last updated: January 25, 2026
Quick Overview
Given a list of intervals, each defined by a start and end point, determine the minimum cost to cover all intervals using a specified cost function. The cost function can vary based on the intervals chosen, and you need to return the minimum total cost required to cover all intervals. The input will consist of a list of intervals and the output should be a single integer representing the minimum cost.
PlanetScale
January 25, 20261
4
4,391 solved
Given a list of intervals, each defined by a start and end point, determine the minimum cost to cover all intervals using a specified cost function. The cost function can vary based on the intervals chosen, and you need to return the minimum total cost required to cover all intervals. The input will consist of a list of intervals and the output should be a single integer representing the minimum cost.
This coding problem is frequently asked during Onsite at PlanetScale. The interviewer is testing your ability to translate a problem into clean, working code while discussing time and space complexity. PlanetScale expects candidates to write production-quality code, not just solve the puzzle.
What the Interviewer Expects
- Recognize the underlying problem pattern (sliding window, two pointers, BFS/DFS, etc.)
- Discuss multiple approaches and trade-offs before coding
- Implement an optimal solution with clean, production-quality code
- Handle all edge cases including boundary conditions and invalid input
- Optimize both time and space complexity with clear justification
- Test your solution systematically with well-chosen examples
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 parallelize this solution?
- How would you test this solution thoroughly?
- Can you optimize the space complexity of your 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 solve the problem of finding the minimum cost to cover all intervals, we can recognize that this is a classic interval covering problem. The underlying pattern here can be approached using a combin...
Approach
- Sort the Intervals: First, we will sort the list of intervals based on their start points. This allows us to efficiently process overlapping intervals.
- Initialize Variables: Create varia...
Submit Your Answer
