64 questions · from 18 interviews
Ebay interview questions
Every question candidates reported from their Ebay interviews, most frequently asked first. Each links to the write-up it came from, so you can see the round and how it went.
Ebay coding and DSA questions
- 01
Container With Most Water
Given an array heights where each element represents the height of a vertical line, pick two lines to act as the walls of a container. Return the maximum area (amount of water) the container can hold.
Medium · From eBay | SDE-2 interview experience | Virtual
- 02
Daily Temperatures
Given an integer array temps representing the daily temperatures, write a function to calculate how many days you need to wait after each day to get a warmer temperature. Return an array answer where answer[i] is the number of days you have to wait for a…
Medium · From eBay | SDE-2 interview experience | Virtual
- 03
Find the K Smallest Elements from Multiple Sorted Arrays
Given multiple sorted arrays, return the k smallest elements across all arrays. The candidate first inserted all elements into a min‑heap and popped the smallest element k times, then optimized by maintaining a pointer for each array to achieve a more…
- 04
Search in a Rotated Sorted Array
Given a rotated sorted array, find the index of a target value. The candidate first described a two‑step method (find the pivot then binary search the appropriate half) and was asked to provide a single‑pass binary search solution.
- 05
Longest Substring Without Repeating Characters
Given a string s, find the length of the longest substring without repeating characters.
Medium · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 06
Word Break II
Given a string s and a dictionary of strings wordDict, add spaces in s to construct a sentence where each word is a valid dictionary word. Return all such possible sentences in any order.
Hard · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 07
Longest Increasing Subarray
Find the length of the longest contiguous subarray in which the elements are strictly increasing.
Medium · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 08
Stack Implementation Using Linked List
Implement a stack data structure using a linked list, supporting standard operations like push, pop, peek/top, and isEmpty.
Medium · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 09
Queue Implementation Using Stack
Implement a queue data structure using two stacks, supporting standard operations like enqueue, dequeue, front, and isEmpty.
Medium · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 10
Longest Palindromic Substring
Given a string s, return the longest palindromic substring in s.
Medium · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 11
N-Queens II
The n-queens puzzle is the problem of placing n queens on an n x n chessboard such that no two queens attack each other. Given an integer n, return the number of distinct solutions to the n-queens puzzle.
Hard · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 12
Valid Parentheses
Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.
Easy · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 13
String Merge with Custom Character Ordering Based on Frequency
Merge two strings such that the resulting string follows a custom ordering based on the frequency of characters from both strings. Use a two-pointer approach with time complexity O(n + m).
Medium · From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 14
Design Data Storage System with Backup Support
Implement a data storage system that supports: SETORINC(key, field, value) : Sets or increments a field under a key. GET(key, field) : Retrieves a field value. DELETE(key, field) : Deletes a field or key. FETCH(field, value) : Returns keys whose specified…
Hard · From eBay SWE Assessment (Industry Coding Assessment)
- 15
Remove Kth Node From End of Singly Linked List
Given the head of a singly linked list and an integer k , remove the k th node from the end of the list and return the head of the modified list.
Medium · From Ebay SE3 interview experience
- 16
Generate Unique Permutations of Digits
Given an array of digits (which may contain duplicates), generate all unique permutations of the array.
Medium · From Ebay SE3 interview experience
- 17
Delete nth node from end of a transaction log (linked list)
You are given a transaction log that is append‑only. At any point there could be a fraudulent transaction happening and you only know its position. You need to remove that transaction from the log. You are not given the starting point and you cannot traverse…
- 18
Parse HTML/XML file into an n‑ary tree
You're given an HTML/XML file with many markup tags, possibly nested. Write a parsing function that reads the file and constructs an n‑ary tree representing the markup hierarchy. Additionally, design functions to addNode, deleteNode, and updateData in the…
- 19
Number of Islands
Given a 2D grid map of '1's (land) and '0's (water), count the number of distinct islands. An island is formed by connecting adjacent lands horizontally or vertically. The problem requires traversing the grid using DFS/BFS to mark visited cells and increment…
Medium · From Ebay SDE-3 Interview Experience - Ebay Live
- 20
Find Largest Island in Grid
Given a 2D grid representing land (1) and water (0), find the area of the largest island. An island is formed by connecting adjacent lands horizontally or vertically. I had to explain the complete logic on the board, perform a dry run, and write the full code.
Medium · From ebay SE-3 Interview Experience
- 21
Lowest Common Ancestor
Find the lowest common ancestor (LCA) of two given nodes in a binary tree. I had to explain the complete logic on the board, perform a dry run, and write the full code.
Medium · From ebay SE-3 Interview Experience
- 22
Implement LRU Cache
Discuss the approach for implementing an LRU Cache.
Medium · From ebay SE-3 Interview Experience
- 23
In-memory Database Implementation
Implement a complete in-memory database with the following levels and an provided interface skeleton: Level 1: Support basic operations to manipulate records, fields, and values within fields. Level 2: Support displaying a record's fields based on a filter.…
- 24
Reverse Pairs
Given an integer array nums, return the number of reverse pairs in the array. A reverse pair is defined as a pair (i, j) such that: • 0 • nums[i] 2 nums[j] Example: Input: nums = [1,3,2,3,1] Output: 2 Explanation: The reverse pairs are: • (1,4)…
- 25
Find Maximum Balanced Sum Subarray
Find the maximum “balanced sum” subarray where a “balanced sum” is defined as a subarray where the sum of the first half equals the sum of the second half. Note that the subarray length must be even. Follow-up: If one “adjustable element” is allowed within…
19 more in the Ebay write-ups.
Ebay system design questions
- 01
LunchDrop System Design
Design an application called LunchDrop, primarily used by corporate employees to order food at their workplace. The application will have a list of restaurants and their menus, with the available restaurants rotating on a daily basis. Users should be able to…
- 02
eBay Top Items and Categories Dashboard Design
Design a dashboard which shows the top 10 items and top 10 categories in eBay by number of quantities sold. Explain the item quantity aggregator and category aggregator, how the system determines current quantity, write frequencies to the state store, pros…
- 03
System Design - What Happens When You Type google.com
Explain what happens behind the scenes when you type 'google.com' into your browser and press enter.
From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 04
TCP vs UDP vs QUIC
Compare and contrast TCP, UDP, and QUIC protocols including their use cases and characteristics.
From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 05
HTTP Status Codes and SRE Alerting
Discuss various HTTP status codes and how they relate to SRE practices such as alerting mechanisms.
From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 06
Kubernetes Concepts Deep Dive
Deep dive into Kubernetes concepts relevant to running scalable services reliably.
From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 07
Toil Reduction Example
Provide an example of reducing operational toil through automation or process improvement.
From eBay Bangalore — Cloud SRE Interview Experience (All Rounds)
- 08
Design persistent storage for millions of ad click events
Design a SaaS product that can ingest millions of ad click events and provide persistent storage. The system should support a queryByAdIdAndUserId() functionality. You cannot use any existing database; you must design the storage mechanism yourself.
- 09
Design Dropbox‑like System
Design a cloud storage service similar to Dropbox. Discuss components such as client‑side syncing, file metadata service, storage back‑end, replication, consistency, scaling, security, and APIs. Justify design decisions and handle typical follow‑up questions…
- 10
Design TinyURL
Design a system like TinyURL for shortening URLs. The discussion primarily focused on high-level design aspects and took around 45 minutes.
Hard · From ebay SE-3 Interview Experience
- 11
Design TinyURL System
Design a system that generates a short URL from a given long URL and converts a short URL back to the original long URL. Considerations included uniqueness, collision handling, scalability, and potential optimizations. I also had to explain my choice of…
Hard · From eBay || SWE3 Interview Experience || Bangalore
- 12
How to Productionize a System
Discussion on the process and considerations for taking a system into production.
- 13
How to Scale a System
Discussion on strategies and techniques for scaling a system.
- 14
Metrics for API Building and Testing
What metrics should be looked for when building and testing an API?
- 15
Design an Online Flash Sale System
Design an online flash sale system. The design should cover deep-level API calls, and incorporate mechanisms for handling concurrency, such as mutexes, optimistic locking, and pessimistic locking.
Hard · From Ebay Senior Software Engineer Interview Experience
- 16
Project-based Scenario Questions
I was asked about the projects I’ve worked on at my current company. Based on that, the interviewer gave me a few scenario-based questions and asked how I would approach or implement them.
Ebay other questions
- 01
Display Static List of Articles (Android/Compose)
The first level required the application to display a static list of articles using predefined data. The challenge was exacerbated by the IDE not providing package name suggestions for Composables like LazyColumn, Column, Text, DP, padding, necessitating…
- 02
Fetch Data from Live API using KTOR and Coroutines (Android)
The second level involved fetching data from a live API using KTOR and Coroutines within the Android application.
- 03
Implement Image Loading Support (Android)
The third level required implementing image loading support in the application.
- 04
GenAI Tools Related Questions
Some general questions related to GenAI tools.
Ebay interview questions FAQ
What questions are asked in Ebay interviews?
Candidates reported 64 distinct questions across 18 Ebay interviews. 44 coding and DSA questions, 16 system design questions, 4 other questions.
How difficult are Ebay interview questions?
Of the questions candidates rated, 9% were easy, 63% medium and 29% hard.