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

JuniorPending
Jun 2026

Summary

Took the Flipkart Software Engineer OA and it was a mixed bag. Two DSA questions, one SQL, and one mandatory Python question. Passed most test cases but couldn't figure out why certain ones failed since no failing input was shown, which is the most frustrating part of any OA.

Questions Asked (4)

Q1

Solve a tree-based problem (easy to medium difficulty).

Algorithms & Data Structures
Author's notes

Passed 10 out of 12 test cases and genuinely have no idea what went wrong with the other two.

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AI HintsAI Generated

Suggested Approach

First, clarify the problem and edge cases, then discuss recursive and iterative approaches with their trade-offs. Choose the most efficient solution based on constraints, and analyze time and space complexity.

Pro tip: Mention how you would handle large trees to avoid stack overflow, showing awareness of production constraints. Also, relate the problem to real-world scenarios like file systems or organizational hierarchies to demonstrate practical thinking.

1. Understand the Problem

Ask clarifying questions to confirm the tree type, input format, and expected output. Identify edge cases such as empty tree, single node, skewed tree, and duplicate values.

2. Explore Approaches

Discuss both recursive (DFS) and iterative (BFS/stack) solutions. Compare their time and space complexities, and consider if the tree is a BST for optimized solutions.

3. Choose and Implement

Select the optimal approach based on constraints and explain your choice. Write clean code with meaningful variable names, handling edge cases explicitly.

4. Test and Validate

Walk through the code with sample inputs, including edge cases. Verify correctness and complexity, and discuss potential optimizations or trade-offs.

Key Points to Mention

  • Tree traversal techniques: DFS (pre-order, in-order, post-order) and BFS (level-order)
  • Recursion vs iteration: trade-offs in terms of code simplicity, stack space, and performance
  • Time and space complexity analysis (e.g., O(n) time, O(h) space for recursion)
  • Handling edge cases: null root, single node, skewed tree, and large trees
  • Use of auxiliary data structures like queues, stacks, or hash maps
  • Applicability to BST properties (e.g., in-order traversal yields sorted order)

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

Q2

Write a SQL query to solve a medium-difficulty data problem.

Data Modeling
Author's notes

Clean 5/5 on this one.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem statement and expected output, then outline your query logic step-by-step before writing SQL. Focus on correctness, efficiency, and handling edge cases, and explain your reasoning as you go.

Pro tip: Always discuss indexing and query performance implications, especially for large datasets typical at Flipkart. Mention how you would test the query with sample data to validate edge cases.

1. Clarify Requirements

Ask questions to understand the exact problem, input tables, expected output, and any constraints (e.g., time range, duplicates).

2. Outline Approach

Break down the problem into logical steps: identify necessary tables, joins, filters, aggregations, and window functions if needed.

3. Write Query

Construct the SQL query incrementally, starting with FROM and JOINs, then WHERE, GROUP BY, HAVING, and finally SELECT with any window functions.

4. Optimize and Validate

Review for performance (e.g., avoid SELECT *, use appropriate indexes) and mentally test with edge cases like NULLs, duplicates, or empty results.

5. Explain and Discuss

Walk through the query, explain key decisions, and discuss potential alternatives or trade-offs.

Key Points to Mention

  • Proper use of JOINs (INNER, LEFT, etc.) and understanding of join conditions
  • Aggregation functions (SUM, COUNT, AVG) and GROUP BY/HAVING clauses
  • Window functions (ROW_NUMBER, RANK, LEAD/LAG) for advanced analytics
  • Handling NULL values and edge cases (e.g., empty groups, duplicates)
  • Query performance considerations: indexing, avoiding full table scans, using EXPLAIN
  • Readability: using CTEs or subqueries for clarity, consistent formatting

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

Q3

Solve a coding problem that must be implemented in Python.

Algorithms & Data Structures
Author's notes

Skipped it entirely.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem constraints and edge cases, then discuss potential approaches and their trade-offs before coding. Implement the optimal solution in clean Python, explaining your reasoning as you go, and test with examples.

Pro tip: At Flipkart, interviewers value candidates who proactively discuss time and space complexity and consider scalability. Always mention how your solution would handle large inputs and potential optimizations.

1. Understand the Problem

Ask clarifying questions to fully grasp the problem requirements, constraints, and edge cases. Confirm input/output formats and any assumptions.

2. Discuss Approaches

Brainstorm multiple solutions, from brute force to optimized, and analyze their time and space complexities. Choose the best approach based on constraints.

3. Implement the Solution

Write clean, modular Python code with meaningful variable names. Explain your logic as you code and handle edge cases.

4. Test and Validate

Walk through your code with sample inputs, including edge cases, to verify correctness. If time permits, discuss potential optimizations or alternative implementations.

Key Points to Mention

  • Time and space complexity analysis of the chosen approach
  • Edge cases such as empty input, large input, duplicates, or negative numbers
  • Trade-offs between different algorithms (e.g., sorting vs. hashing)
  • Use of Python-specific features like list comprehensions, generators, or built-in functions
  • Modularity and readability of code
  • Potential scalability issues and how to address them

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

Q4

Solve what appeared to be the easiest DSA question in the assessment.

Algorithms & Data Structures
Author's notes

Only 6 out of 12 passed and this was supposedly the easiest one on the whole OA.

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AI HintsAI Generated

Suggested Approach

Start by restating the problem in your own words and clarifying constraints (input size, edge cases, expected complexity). Then propose the simplest correct solution, analyze its time/space complexity, and discuss potential optimizations or trade-offs. Finally, walk through a small example to validate the approach.

Pro tip: Even if the problem seems trivial, explicitly mention edge cases (empty input, single element, duplicates, overflow) and test your solution mentally. Interviewers at Flipkart value thoroughness and the ability to catch subtle bugs over speed.

1. Clarify the problem

Ask clarifying questions about input format, constraints, expected output, and edge cases. Confirm your understanding with the interviewer.

2. Discuss brute force and optimal approach

Outline a naive solution first, then explain how you can improve it. Mention time and space complexity for each.

3. Write clean code

Implement the chosen approach with meaningful variable names and modular structure. Handle edge cases explicitly.

4. Test with examples

Walk through a few test cases, including edge cases, to verify correctness. Dry-run the code step by step.

5. Analyze and optimize

State the final complexity and discuss any further optimizations or trade-offs, even if not needed.

Key Points to Mention

  • Time and space complexity analysis (Big-O notation)
  • Edge cases: empty input, single element, duplicates, large values
  • Trade-offs between different approaches (e.g., hash map vs sorting)
  • Correctness proof or invariant for the algorithm
  • Potential follow-up questions or variations
  • Code readability and maintainability

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