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IBM·Software Engineer·Online Assessment (OA)·Junior

JuniorPending
Aug 2026

Summary

Did the IBM SWE intern OA which had two parts: a standard leetcode problem and a repo debugging task. Passed all test cases on both and now have no idea if that actually means anything.

Questions Asked (2)

Q1

Solve a coding problem similar to a standard LeetCode-style algorithm question.

Algorithms & Data Structures
Author's notes

Passed all the test cases so I guess it went fine.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem constraints and edge cases, then discuss a brute-force solution before optimizing with appropriate data structures and algorithms. Walk through your thought process, analyze time and space complexity, and finally implement clean, modular code with test cases.

Pro tip: Verbalize your reasoning and trade-offs even if you don't finish coding—interviewers at IBM value clear problem-solving and communication over silent perfection. Also, proactively mention how you'd test your solution with edge cases and scale it for large inputs.

1. Understand and Clarify

Restate the problem in your own words, ask clarifying questions about input size, constraints, and edge cases, and confirm expected output format.

2. Explore Approaches

Discuss a brute-force solution first, then propose optimized approaches using suitable data structures (e.g., hash maps, heaps, two pointers) and explain trade-offs.

3. Plan and Analyze

Outline the chosen algorithm step-by-step, analyze time and space complexity, and justify why it's optimal for the given constraints.

4. Implement and Test

Write clean, modular code with meaningful variable names, then walk through test cases including edge cases to verify correctness.

5. Review and Optimize

Check for off-by-one errors, discuss potential improvements or alternative solutions, and mention how you'd handle scalability if needed.

Key Points to Mention

  • Clarify problem constraints and edge cases before coding
  • Start with a brute-force solution and then optimize
  • Choose appropriate data structures and justify their use
  • Analyze time and space complexity of the solution
  • Write clean, readable code with meaningful names
  • Test with edge cases and discuss scalability

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.

Q2

Given a repository with bugs, identify and fix the issues to make the code work correctly.

Algorithms & Data StructuresRoot Cause Analysis
Author's notes

This one was more interesting than I expected.

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AI HintsAI Generated

Suggested Approach

Start by understanding the expected behavior and reproducing the bugs with test cases. Then systematically debug each issue, fix them, and verify with tests to ensure correctness.

Pro tip: Communicate your thought process clearly and prioritize fixes based on impact; show that you can balance thoroughness with time constraints.

1. Understand Requirements

Clarify the expected behavior of the code and identify what 'correct' means. Review any documentation or tests to understand the intended functionality.

2. Reproduce and Identify Bugs

Run the code with various inputs to reproduce the bugs. Use debugging tools and log statements to pinpoint the root causes of each issue.

3. Prioritize and Fix

Address bugs in order of severity or dependency, making minimal changes to fix each issue without introducing new problems.

4. Test and Validate

After each fix, run tests to ensure the bug is resolved and no regressions occur. Add new tests if necessary to cover edge cases.

5. Review and Refactor

Review the changes for code quality and consider refactoring if the fixes are hacky. Ensure the solution is maintainable and efficient.

Key Points to Mention

  • Systematic debugging approach
  • Root cause analysis
  • Writing and running unit tests
  • Edge case handling
  • Code readability and maintainability
  • Version control and incremental commits

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.