Walmart Low Level Design Interview Questions

Walmart has 3 rounds of interviews DSA, LLD, HLD. 2nd or 3rd round is LLD. In some cases there are two DSA rounds or DSA round + round with lots of small questions including LLD, springboot, concurren

Walmart has 3 rounds of interviews DSA, LLD, HLD. 2nd or 3rd round is LLD. In some cases there are two DSA rounds or DSA round + round with lots of small questions including LLD, springboot, concurrency, java etc. After you give a LLD solution HLD discussion also happen like database schema, scaling etc. For Software engineer 3 roles any given round it is more of LLD solution followed with some basic HLD discussion. It also includes concurrency, locking discussions. In LLD, clear explanation of design choices mattered more than just coding. --------------------------------------------------- Also for Walmart observer design pattern occurred most frequently (directly or indirectly) in LLD questions and in short discussions. So if you have good understanding of observer pattern(which is easy) then your chances improve. Not only they ask LLD problems but there may even be explicit discussion about common design patterns and how you will solve some sample use cases using those design patterns. Observer, Strategy, factory, command and singleton design pattern feature frequently in discussions. For example, a common discussion is how will you implement a notification system using observer or different payment methods in a payment gateway using strategy design pattern. This blog has some of the design patterns and how they are used to solve different usecases <a href="https://medium.com/@prashant558908/4-most-common-design-patterns-that-are-essential-to-solve-low-level-design-interview-questions-b7196c8c2b8by

Shopping Cart that uses an initial item catalog and lets a user add items by ID, view their cart, and checkout. It also enforces unknown item ID, insufficient stock, and empty-cart checkout. Practice Link: <a href="https://codezym.com/question/41y

Connection Pool that maintains a fixed number of reusable connection objects. Connections are indexed as integers: 0, 1, 2, ... capacity - 1. Clients requests a connection using a requestId. If a free connection exists, it is assigned immediately. If no free connection exists, the request is placed into an internal queue and will wait until a connection becomes free. The internal queue is

FIFO (first-come-first-serve): whenever a connection is released, it is immediately assigned to the oldest queued request. Practice Link: <a href="https://codezym.com/question/49y

Custom HashMap that stores String keys and String values. You must implement buckets, a custom hash, collision handling (multiple keys in the same bucket), and rehashing (resizing and redistributing entries). Goal of this problem is to force you to do a custom hashmap implementation, So don't use any inbuilt set/map/dictionary in your implementation. Practice Link: <a href="https://codezym.com/question/43.

Please upvote this post to give it better reach. Wish you the best of luck for your interview prep. ----------------------------------------