Validate grid sorted

Last updated: August 27, 2025

Quick Overview

Determine if a given grid satisfies the balanced property.

Postmates
Coding & Algorithms
Machine Learning Engineer
Postmates
August 27, 2025
Machine Learning Engineer
Phone Screen
Coding & Algorithms
Medium

172

11

707 solved


Determine if a given grid satisfies the balanced property.

This coding problem is frequently asked during Phone Screen at Postmates. The interviewer is testing your ability to translate a problem into clean, working code while discussing time and space complexity. Postmates 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
Tree structures and recursion
Edge cases and input validation
Common algorithm patterns (sliding window, two pointers, BFS/DFS)
Dynamic programming and memoization
Time and space complexity analysis
How to Approach This
  1. Clarify input constraints and edge cases before writing code.
  2. Walk through your approach verbally and confirm with the interviewer before coding.
  3. Start with a brute force solution, then optimize. Mention time and space complexity.
  4. Test your solution with examples, including edge cases like empty input or duplicates.
  5. 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?
  • Can you solve this in a single pass?
  • What is the worst-case input for 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 Problems
Sample Answer
Problem Analysis

To determine if a given grid satisfies the balanced property, we need to ensure that each row and each column is sorted in non-decreasing order. This problem can be approached using a straightforward ...

Approach
  1. Iterate through each row: For each row, check if the elements are sorted. This can be done by comparing each element with the next one in the same row.
  2. Iterate through each column: After...

Submit Your Answer
Markdown supported

Related Questions