Reddit Software Engineer Interview Questions

Word Search II Given a 2-D grid of characters `board` and a list of strings `words`, return all words that are present in the grid. For a word to be present it must be possible to form the word with

Dictionary Word Transformation Path ## Problem Overview You are given: * a `start` word * a `target` word * a dictionary of allowed words Determine whether the words can be connected by a valid tran

Report Chain ## Problem Overview You are given an org chart as a `list[list[str]]`. Each inner list has the form: ```python [manager, report_1, report_2, ...] ``` For example: ```python [["A", "B",

Tennis Score Game ## Problem Overview Design a two-player game with three core methods: * `add_score(player)` * `get_score()` * `get_result()` The interview then adds a follow-up: convert the score

Design a Gaming Leaderboard Service Imagine you are building a backend service for game studios. Games run on players' computers, and after a game session ends the client wants to show two things ri

Design Reddit Live Chat Design Reddit Live Chat for large live events such as the Super Bowl. Users join a live discussion tied to a post or event, receive messages in real time, send messages if al

Moderator List Hierarchy ## Problem Overview Implement a Reddit-style moderator list from a newline-delimited log string. The interview usually comes in three parts: 1. A single mod list 2. Multiple

Merge Chat Message Windows ## Problem Overview You are given an existing API: ```python def get_chat_messages(message_id: int) -> list[Message]: ... ``` For a given `message_id`, it returns the surr

Logger Rate Limiter Design a logger system that receives a stream of timestamped messages. A message may be printed only if the same message has not been printed in the last `10` seconds. Implement

Billing Status Replay (OOD) ## Problem Overview We accidentally dropped the database that stored the current billing state for advertisers. The old transaction logs still exist, so the task is to re

Multi part question from reddit tech screen. The problem should be code complete and should successfully execute the given test cases. Verdict: Reject interview time : 60 min Feedback:- Question has a lot...

Hi Reddit, I’ve been practicing LeetCode problems after work in my spare time. While it isn't easy to solve them, but even hard part is remembering them. I don’t really have a solid review routine, so

I have a datadog on site coming up soon and I\'ve seen a few people posted this as their system design question on glassdoor Description: Design an app in the style...

About a month ago I posted about [my project](https://puter.com/app/editor?c=1) on /r/programming ([the post](https://www.reddit.com/r/programming/comments/v45rb6/i_spent_a_year_building_a_desktop_env

The phone screen was over google hangouts plus a code sharing site. The first part of the interview was general knowledge. Again, this is front end. What is cross site...

So, this happened, I got rejected for- having a reddit account and being unbelievably stupid. I am Senior software engineer and was interviewing for a startup which just got huge funding. I got throug

LeetCode #127: Word Ladder. Difficulty: Hard. Topics: Hash Table, String, Breadth-First Search. Asked at Reddit in the last 6 months.

I’m looking to understand this from the point of view of experienced devs who have worked initially at non-recognizable firms and then made the switch to recognizable tech or non-tech companies. **Has

I’ve read a lot on Reddit threads that the only way to be an effective software engineer with AI is to learn system design and communicate well. I have two questions: 1. I don’t have much experience i

I see this so much on Reddit lately, people will cram some percentage value in every single bullet point on their resume, "reduced downtime by %20", "increased throughput by 10%", "improved X by Y%" I