Apple

Basic Calculator II

Best Time to Buy and Sell Stock

Also asked at Amazon, Google +3

Course Schedule

Also asked at Amazon, TikTok

Course Schedule II

Also asked at MongoDB, Snowflake

Design a Distributed Message Queue

Also asked at Amazon, Confluent

Design a File Backup System

Also asked at Dropbox, Meta +1

Design a Zero-Downtime Data Migration

Design an Ad Event Aggregator

Also asked at Meta, Netflix +2

Design an Authorization System (RBAC + Resource-Level)

Also asked at Atlassian

Design an Enterprise AI Agent with Internal Tool Access

Also asked at Google

Design Distributed Metrics System

Also asked at Google, LinkedIn +1

Design Search Typeahead

Also asked at Amazon, LinkedIn +4

Find First and Last Position of Element in Sorted Array

Also asked at Meta

Group Anagrams

Also asked at Affirm, Amazon +2

Insert Delete GetRandom O(1)

Also asked at Affirm, LinkedIn +1

Longest Common Prefix

Also asked at Google, Jane Street +1

Merge Intervals

Also asked at Amazon, Atlassian +9

Merge K Sorted Lists

Also asked at Amazon, Meta +5

Points of Interest (POI) System / Yelp

Also asked at OpenAI

Reverse Integer

Also asked at Google

Reverse Linked List

Snapshot Array

Also asked at MongoDB

Subarray Product Less Than K

Subarray Sum Equals K

Also asked at Amazon, Google +1

Two Sum

Also asked at Airbnb, Amazon +5

Valid Palindrome

Also asked at Meta