OpenAI Coding Interview Questions

Plants on a grid catch an infection from their neighbours; simulate it day by day. The grid holds infected 'X', healthy '.'…

Implement a GPU credit tracker, GPUSolution, with three methods: - add(grant_id, amount, timestamp, expire): grant amount credits, usable from timestamp up to…

Before the round, the recruiter's prompt names it ML Debug: a transformer model written in PyTorch whose bugs you find and fix.…

The round is one problem in two graded parts, in a 60-minute round where reports give a length. Thirty-four reports. Reports that…

Build an in-memory database you query through method calls. There is no framework: you write and test everything yourself. One candidate says…

Implement a key-value store whose shutdown() writes everything to a file store and whose restore() reads it back, so a fresh instance…

Build a SocialNetwork class in which users follow and unfollow each other and you can take snapshots of the follow graph, then…

You are given an n-ary tree in which every node is a machine in a cluster. A node knows its own id,…

The recruiter's prompt for this round, as a candidate quoted it: "We'll spend the session writing machine-learning code—training a classifier and exploring…

Reports call this round a refactoring exercise; one candidate says the recruiter's prompt was "make improvements to some basic existing code". It…

Simulate a battle between two teams of monsters and produce an event log. Sixteen reports name this question, at the phone screen…

Implement IPv4 address iterators in Python with the standard iterator protocol: __init__, __iter__ and __next__. Reports describe a 60-minute round, asked both…

A 60-minute ML coding round in three parts: one-nearest-neighbour in NumPy with no loops, the same prediction as a neural-network forward pass,…

The round is one problem the interviewer extends, a 75-minute phone screen in every report whose poster gives a length (a commenter…

A 75-minute general coding round in which the tests reveal the problem. Eight candidates report it and four describe it in detail;…

This is the ML coding round on prefix products of matrices. Six reports between April and August 2026 describe it, three of…

The round is one problem in two graded parts, on the 60-minute general coding round. Five candidates report it. Four describe it…

Design a resumable iterator: an iterator whose position you can save and later restore, so that reading picks up exactly where the…

You are given a vector of logits (raw, unnormalized scores). Compute the Shannon entropy of the softmax distribution they define: p_i =…

A card game, reported as a "poker simulation" and as a new question from late August 2026. Each player is dealt three…

Implement a fault-tolerant work queue, WorkQueue. The reports describe the queue and then a dependency follow-up that has to be coded, so…

Build a rating card component in Kotlin Compose with rating and comment fields (both required before submission). Display success message after submit.…

A debugging round. You get a small Django app serving a dummy version of ChatGPT, and its rate limiter does not work.…

Parse instrument name and beat sequence (binary-like notation where '1 0' = half note, '1 1' = two quarter notes),…

Implement a Spreadsheet class with two methods, set_cell(key, value) and get_cell(key) (the reports write them setCell and getCell). A cell holds either…

OpenAI phone screen reportedly includes bitwise operations question. HR confirmed it is an algorithms problem…

Part 1 (known problem): Given multiple shards with overlapping thresholds, output rebalanced shards minimizing data movement; solved using mini heap to maintain…

Implement a 'cd' command that handles relative paths with special cases ('../A/B/', './A/', '../A/B/../', etc.). Write a cd() method that simplifies…

Similar to LeetCode 289. Approximately 5 sub-questions total. Requires careful attention to clarifying questions as some standard assumptions may change during the…

Given an m×n grid where each cell is one of '.', '#', or '', find the shortest path that visits all ''…

Given a 2D array of integers and a value maxsum, find the maximum size k such that every possible k×k square sub-grid…

Build a React component mimicking the ChatGPT UI (input box, message flow, loading states, streaming response handling).…

Starting from a given number, at each step you can add any element from an array and take modulo. Find minimum steps…