Flipkart

Role: SDE-1

College: Not Specified

Interview Date: October 2020 (Online Aptitude a month prior)

Interview Type: Off-Campus

Result: Implied Selected (Got call for managerial round within 40 mins after Technical 2)

Difficulty: Online Assessment (Medium to Hard), Technical (Varied, some difficult optimizations), Managerial (HR-based, subjective)

Rounds: 4 rounds (Online Assessment, Technical Interview 1, Technical Interview 2, Managerial Round)

Topics Asked: Array sorting, Hashmap-based problems, Advanced String matching, Squares of a sorted array, Maximize sum of k elements by taking corner elements (optimized to O(k)), Reorder array according to given indexes (constant space, repeated k times), Find row with maximum 1s (O(m*n), O(mlogn), O(m+n) approaches), Generic string grouping with hash function (prime number based hash), HR/Behavioral questions.

Experience:

The process began with an Online Aptitude test (AMCAT Smart Meet Platform) with 3 questions. The candidate solved two completely and passed 4/21 test cases for the third. The questions included sorting first k elements increasing and others decreasing, a medium hashmap-based question, and an advanced string matching question (similar to LeetCode "Draw String").

Round 2: Technical Interview 1 (October 2020). Three questions were asked after introductions: 1. Squares of a sorted array (pseudocode expected). 2. Maximize sum of k elements in an array by taking only corner elements. The candidate gave a recursive brute force (O(2^k)) and was asked to optimize, remembering an O(k) solution and writing the code. 3. Reorder array according to given indexes. The candidate quickly explained the constant solution, which satisfied the interviewer. An extension was asked to repeat the process 'k' times without extra space, but time ran out.

Round 3: Technical Interview 2 (October 2020, 1-day break). This round had no introduction, straight to coding. 1. Find the row with the maximum number of 1s in a binary matrix. The candidate provided three approaches: naive O(m*n), binary search on each row O(mlogn), and an O(m+n) approach. The O(m+n) approach was discussed in detail, including time complexity, and no code was needed. 2. A generic string grouping question where a hash function was needed to distinguish groups. The candidate gave a string-based hash, then a prime number-based integer hash, which didn't fully satisfy the interviewer due to time constraints.

Round 4: Managerial Round. This was a pure HR-based round with usual behavioral questions. The candidate asked questions about Flipkart's inner workings.