Amazon Software Development Engineer (SDE) interview questions

Algorithm & Coding: “Find the longest substring without repeating characters.” “Merge k sorted linked lists.” “Implement an LRU cache.” “Given a binary tree, return its level order traversal.” “Find the kth largest element in a stream.” Design & System Thinking: “Design a URL shortener like TinyURL.” “Design a scalable notification system that supports millions of users.” “How would you use design patterns like Singleton or Observer in a real project?” “How do you ensure fault tolerance and scalability in a distributed system?” Behavioral / Teamwork: “Tell me about a time you disagreed with a teammate — how did you handle it?” “Describe a time you took ownership of a problem beyond your scope.” “Give an example of when you delivered under tight deadlines.” “Tell me about a time you improved a process or system in your team.”