PayPal Low Level Design Interview Questions

PayPal asks LLD question in their role specialization round many times. So, if a role specialization round is scheduled then confirm with recruiter whether this will be a LLD round. There can be multi

PayPal asks LLD question in their role specialization round many times. So, if a role specialization round is scheduled then confirm with recruiter whether this will be a LLD round. There can be multiple LLD rounds or a mix of LLD+HLD round. Some HLD rounds may have questions like design LRU cache or design parking lot, ticket booking system etc. These start with basic low level implementation (e.g. using HashMap and Doubly Linked List in case of LRU cache) and then move to scaling the whole thing. I am listing the top low level design questions that you will come across during PayPal interviews. I have built this list from recent interview experiences of candidates. ---------------------------------------- PS: Ask me any Low-Level Design Interview related questions on r/LowLevelDesign All Questions List: <a href="https://codezym.com/lld/paypal

Return the value of the key if the key exists, otherwise return -1. void put(int key, int value) Update the value of the key if the key exists. Otherwise, add the key-value pair to the cache. If the number of keys exceeds the capacity from this operation, evict the least recently used key. For LFU cache, when the cache reaches its capacity, it should invalidate and remove the least frequently used key before inserting a new item. LRU cache: <a href="https://leetcode.com/problems/lru-cache/.

Follow-up: Also implement edit methods like character insertion, deletion. Practice Link: <a href="https://codezym.com/question/40e

Observer pattern (Queue Manager = Subject, Subscribers = Observers). Practice Link: <a href="https://codezym.com/question/33-