Sliding Window on string
Last updated: January 2, 2026
Quick Overview
Given a string, implement a sliding window technique to find the length of the longest substring without repeating characters. The function should take a string as input and return an integer representing the length of the longest substring that meets the criteria.
Databricks
January 2, 2026190
15
4,742 solved
Given a string, implement a sliding window technique to find the length of the longest substring without repeating characters. The function should take a string as input and return an integer representing the length of the longest substring that meets the criteria.
Coding interviews at Databricks focus on problem-solving approach as much as the final solution. The interviewer wants to see you break down the problem, consider edge cases, and optimize iteratively. Communication throughout the process is key.
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
- Can you optimize the space complexity of your solution?
- What if the input doesn't fit in memory?
- What is the worst-case input for 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 length of the longest substring without repeating characters, we can use the sliding window technique. This approach is suitable here because we need to dynamically...
Approach
- Initialize two pointers:
startandend, both set to the beginning of the string. These pointers will represent the current substring's boundaries. - Use a hash map (or dictionary) to store the...
Submit Your Answer
