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AT&T·Software Engineer·Technical Phone Screen·Junior

JuniorRejected
Jun 2026

Summary

Failed a technical phone screen after making some syntax and naming convention mistakes that the interviewer counted against me, even though I nailed the complexity analysis. Still not sure if I agree with the feedback, but here we are.

Questions Asked (1)

Q1

Solve an algorithmic problem and analyze its time and space complexity.

Algorithms & Data Structures
Author's notes

Got the right approach and explained the complexity fine at the end, which felt good.

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AI HintsAI Generated

Suggested Approach

First, clarify the problem requirements and constraints, then discuss a brute-force solution before optimizing. Implement the optimal solution with clean code, and finally analyze time and space complexity, explaining trade-offs.

Pro tip: Always communicate your thought process and consider edge cases; interviewers value problem-solving skills and clarity over just getting the right answer.

1. Understand the Problem

Ask clarifying questions to confirm input/output formats, constraints, and edge cases. Restate the problem in your own words to ensure alignment.

2. Explore Approaches

Discuss a naive solution first, then propose an optimized approach, explaining the reasoning and trade-offs. Consider multiple data structures and algorithms.

3. Implement the Solution

Write clean, modular code with meaningful variable names. Verbally explain each step as you code to demonstrate understanding.

4. Test and Validate

Walk through the code with a few test cases, including edge cases. Debug any issues and verify correctness.

5. Analyze Complexity

Derive the time and space complexity using Big-O notation. Explain how the complexity scales with input size and any potential optimizations.

Key Points to Mention

  • Clarify constraints and edge cases before coding
  • Start with a brute-force solution and then optimize
  • Explain the choice of data structures and algorithms
  • Write clean, readable code with comments
  • Test with normal and edge cases
  • Analyze time and space complexity using Big-O notation

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