LinkedIn interview questions

Design a Job Scheduler

Design a distributed job scheduler that can handle high-throughput job processing (10,000+ jobs per second), support both scheduled (cron-based) and ad-hoc job execution…

Companies: LinkedIn, Airbnb, Apple, Autodesk +25

System Design

Last reported Aug 2026

Flatten Nested List Iterator

Given a nested list where elements may be integers or sublists, implement a NestedIterator with next() and hasNext() that returns all integers in depth‑first, left‑to‑right…

Companies: LinkedIn, Adobe

Depth-First Search · Design · Iterator · Queue

Last reported Aug 2026

Valid Parentheses

Check whether a string of parentheses/brackets is valid by ensuring every closing bracket matches the most recent unmatched opening bracket and the types and nesting…

Companies: LinkedIn, Amazon, Apple, Bloomberg +9

Bracket Sequences · Stack · String

Last reported Aug 2026

Interval Addition and Next Interval Lookup

Given a set of intervals, implement operations to add new intervals (merging overlapping ones as needed) and find the next interval for a given interval…

Companies: LinkedIn

Last reported Jul 2026

Minimum Robots to Capture Sara

Given a tree of N outposts (2 ≤ N ≤ 7×10⁴) connected by N-1 bidirectional tunnels where leaf nodes are exits, determine the minimum number…

Companies: LinkedIn

Last reported Jul 2026

Motivating a team with low morale

You are joining a new team as an Engineering Manager and discover the team has low morale and motivation. What steps would you take to…

Companies: LinkedIn, Amazon, Google

Last reported Jul 2026

Valid Perfect Square

Determine whether a positive integer is a perfect square without using built-in sqrt — i.e., decide if there exists an integer x such that x*x…

Companies: LinkedIn

Last reported Jul 2026

Find K Pairs with Smallest Sums

Given two non-decreasing arrays, return the k pairs (one element from each) with the smallest sums — the challenge is to efficiently produce the smallest…

Companies: LinkedIn

Array · Heap (Priority Queue)

Last reported Jul 2026

Maximum Depth of Binary Tree

Given the root of a binary tree, return its maximum depth — the number of nodes along the longest root-to-leaf path. This classic easy problem…

Companies: LinkedIn, Google

Binary Tree · Breadth-First Search · Depth-First Search · Tree

Last reported Jun 2026

Course Schedule II

Given numCourses and prerequisite pairs, return any ordering of courses that satisfies all prerequisites or an empty array if impossible — this is essentially computing…

Companies: LinkedIn, Amazon, Anduril, Apple +11

Breadth-First Search · Depth-First Search · Graph Theory · Topological Sort

Last reported Jun 2026

Tallest Tower by Stacking Blocks

Given a collection of block types each defined by a count, weight, and maximum supported weight, determine the maximum number of blocks that can be…

Companies: LinkedIn

Last reported Jun 2026

Longest Balanced Substring With One Swap

Given a binary string s, perform at most one swap between any two characters, then select a substring with an equal number of '0's and…

Companies: LinkedIn

Last reported May 2026

Describe experience working on a complex project

Companies: LinkedIn, Amazon, Arize Ai, Block +12

Last reported Apr 2026

Design a Distributed Blocking/Denylist System

Design a distributed denylist system that blocks requests from specified entities (users, IP addresses, emails, etc.). The system should integrate with external APIs to fetch…

Companies: LinkedIn, Google

Last reported Apr 2026

Is Graph Bipartite

Given an undirected graph as adjacency lists (possibly disconnected), determine whether it is bipartite — i.e., can its vertices be two-colored so no adjacent vertices…

Companies: LinkedIn, Google

Last reported Apr 2026

Longest Substring with At Most K Distinct Characters

Given a string and an integer K, find the length of the longest substring that contains at most K distinct characters. This is typically solved…

Companies: LinkedIn, TikTok

Hash Table · Sliding Window · String

Last reported Apr 2026

Task Scheduler

Given tasks labeled A–Z and a cooldown n, compute the minimum number of CPU intervals (including idles) to finish all tasks so that identical tasks…

Companies: LinkedIn, Amazon, Apple, Databricks +3

Array · Counting · Greedy · Hash Table

Last reported Apr 2026

Tell me about a time you had to pivot mid-project.

Companies: LinkedIn, Capital One, Google, Lockheed Martin +4

Last reported Apr 2026

Serialize and Deserialize Binary Tree

Implement two complementary algorithms to convert a binary tree to a string and back, preserving exact node values and tree structure (including null children) so…

Companies: LinkedIn, Amazon, Meta, Microsoft +2

Last reported Apr 2026

Design a distributed rate limiter

Algorithm trade-offs (fixed window, sliding log, sliding counter, token bucket), placement, distributed atomic counting, failure modes.

Companies: LinkedIn, Amazon, Anthropic, Apple +14

api-gateway · atomicity · Concurrency · Consistency & Availability

Last reported Apr 2026

Connecting Cities With Minimum Cost

Given n cities and a list of undirected weighted connections, find the minimum total cost to connect all cities (or return -1 if it's impossible)…

Companies: LinkedIn, Meta

Last reported Apr 2026

Design a Calendar System

Design a calendar system that allows users to register, manage their schedules, and view other people's availability and free/busy times.

Companies: LinkedIn, Microsoft, Oracle

Last reported Apr 2026