Flipkart Coding Interview Questions
25 Flipkart coding interview problems with full optimal solutions — 11 easy, 11 medium, 3 hard. Every problem ships with multiple approaches (brute-force first, then the optimal), complexity tables for each, company-specific tips on what an Flipkart interviewer values, and a FAQ section.
- #1easyfoundational
1. Two Sum
Find two indices in an array whose values sum to a target — Flipkart uses this to gauge whether candidates default to brute force or reach for hash maps.
- #2easyfoundational
2. Valid Parentheses
Validate that opening and closing brackets are balanced — Flipkart uses this to test stack intuition before scaling to nested order-state machines.
- #3easyfoundational
3. Merge Two Sorted Lists
Merge two sorted linked lists into one sorted list — Flipkart asks this to test pointer manipulation before scaling to merging sorted shipment manifests.
- #4easyfoundational
4. Remove Duplicates from Sorted Array
Strip duplicates in-place from a sorted array — Flipkart uses this to test two-pointer fluency before scaling to deduping customer review streams.
- #5easyfoundational
5. Same Tree
Check whether two binary trees are structurally identical with equal node values — Flipkart uses it to test recursion fluency before diving into category-tree problems.
- #6easyfoundational
6. Symmetric Tree
Decide whether a binary tree is a mirror of itself — Flipkart uses it as a quick recursion warm-up before moving to inventory-tree questions.
- #7easyfoundational
7. Maximum Depth of Binary Tree
Compute the height of a binary tree — Flipkart uses this as a recursion sanity check before harder catalog-tree traversals.
- #8easyfoundational
8. Best Time to Buy and Sell Stock
Find the max single-transaction profit from a price stream — Flipkart maps this to spotting the best discount window during a Big Billion Days sale event.
- #9easyfoundational
9. Single Number
Find the only element appearing once in an array where every other element appears twice — Flipkart uses this as a bit-manipulation gateway before harder dedup problems.
- #10easyfoundational
10. Min Stack
Design a stack with O(1) push, pop, top and getMin — Flipkart uses it to test whether candidates pick auxiliary structures over recomputation on every call.
- #11easyfoundational
11. Reverse Linked List
Reverse a singly linked list iteratively and recursively — Flipkart uses it to confirm pointer hygiene before moving on to LRU-cache style problems.
- #12mediumfoundational
12. LRU Cache
Implement an LRU cache with O(1) get and put — Flipkart asks this because inventory-snapshot lookups during flash sales must hit cache in microseconds.
- #13mediumfoundational
13. Number of Islands
Count connected groups of land cells in a grid — Flipkart maps it to clustering nearby pincodes for warehouse coverage analysis.
- #14mediumfoundational
14. Kth Largest Element in an Array
Find the kth largest value in an unsorted array — Flipkart uses it to test heap vs quickselect fluency, mirroring their search ranking top-K problems.
- #15mediumfoundational
15. Product of Array Except Self
Compute each index's product-of-all-others without division — Flipkart uses it to test the prefix-suffix trick that powers their cross-sell ranking scores.
- #16mediumfoundational
16. Find the Duplicate Number
Find the duplicate in an array of n+1 integers in [1, n] without modifying it — Flipkart maps this to detecting double-charged COD orders in their payments pipeline.
- #17mediumfoundational
17. Top K Frequent Elements
Return the k most frequent values in an array — Flipkart maps this to surfacing the top-K trending SKUs during a Big Billion Days sale event.
- #18mediumfoundational
18. Subarray Sum Equals K
Count contiguous subarrays summing to a target — Flipkart uses it to test the prefix-sum + hash map pattern behind their daily sales-target reporting.
- #19mediumfoundational
19. Daily Temperatures
For each day report how many days until a warmer temperature — Flipkart uses it to test monotonic-stack fluency before harder pricing-window problems.
- #20mediumfoundational
20. Rotting Oranges
Compute the minutes until all fresh oranges rot in a 4-connected grid — Flipkart uses it to test multi-source BFS, the same model behind warehouse stockout propagation.
- #21mediumfoundational
21. Longest Common Subsequence
Find the length of the longest common subsequence of two strings — Flipkart uses it to test 2-D DP fluency, the same shape used for fuzzy product-name dedupe.
- #22mediumfoundational
22. Successful Pairs of Spells and Potions
For each spell strength, count potions whose product meets a success threshold — Flipkart uses this binary-search-on-sorted-array pattern for offer-eligibility checks during sale events.
- #23hardfoundational
23. Sliding Window Maximum
Return the max of every length-k window in O(n) — Flipkart uses it to test deque fluency, the trick behind their per-pincode peak-traffic dashboards during sale spikes.
- #24hardfoundational
24. Find Median from Data Stream
Maintain the running median of a number stream with O(log n) inserts and O(1) lookups — Flipkart uses it for live latency dashboards during Big Billion Days sale-event spike handling.
- #25hardfoundational
25. Modify Graph Edge Weights
Assign positive weights to '-1' edges so the shortest source-to-destination path equals a given target — Flipkart uses it to test Dijkstra fluency for warehouse routing under SLA constraints.