OpenAI data scientist interviews test statistical reasoning, ML model design, SQL proficiency, A/B testing methodology, and Python-based algorithm implementation.
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coding
Hard
Verified Question
#1
1. Count Machines In A Tree
Category: Tree coding problemYou are given a tree-structured network of machines where each node represents a machine. Machines can only communicate with their parent and...Input: String
Output: Computed result
coding
Medium
Verified Question
#2
2. Implement cd Command
Category: Algorithm coding problemImplement a simplified version of the Unix
cd command. Given a current directory path and a relative destination path, return the final absolute...Input: Given inputOutput: Computed result
coding
Medium
Verified Question
#3
3. Largest Subgrid
Category: Grid/matrix coding problemYou are given a 2D grid of non-negative integers and a maximum sum constraint. Find the largest size of a square sub-grid such that all...Input: 2D grid
Output: Integer
coding
Hard
Verified Question
#4
4. Memory Allocator
Category: Linked list coding problem# Memory Allocator Design a memory allocator that manages a contiguous block of memory. Implement
malloc and free operations with efficient...Input: Linked listOutput: Computed result
coding
Hard
Verified Question
#5
5. Toy Language Type Inference
Category: String coding problemImplement a type system for a toy programming language that supports primitives, tuples, and generics. Your task is to represent types and infer...Input: List
Output: Computed result
coding
Medium
Verified Question
#6
6. Virus Spread
Category: Grid/matrix coding problemSimulate the spread of a virus through a grid. Each cell can be in one of three states: healthy, infected, or immune. *This is similar to a leetcode...Input: 2D grid
Output: Integer
coding
Medium
Verified Question
#7
7. Bot-Enabled Messaging System
Category: String coding problemYou are building a chat system that supports human users and automated bots. Messages are added to a channel log and may trigger bot responses. The...Input: List
Output: Computed result
coding
Hard
Verified Question
#8
8. Connection Tracker
Category: Algorithm coding problemDesign a social network system that tracks follow relationships between users and preserves a full history through snapshots. The system allows...Input: List
Output: Computed result
coding
Medium
Verified Question
#9
9. GPU Credit Ledger
Category: String coding problemYou are designing a system to manage GPU credits. Each credit grant is valid during a specific time window. Events may arrive out of chronological...Input: String
Output: Computed result
coding
Medium
Verified Question
#10
10. GPU Credit Manager
Category: String coding problemYou are designing a system to manage GPU credits. Each credit grant is valid during a specific time window. Events may arrive out of chronological...Input: String
Output: Computed result
coding
Hard
Verified Question
#11
11. In-Memory SQL Engine
Category: String coding problemDesign an in-memory SQL database that supports creating tables, inserting rows with automatic type inference, and querying with filtering and sorting.Input: List
Output: Computed result
coding
Hard
Verified Question
#12
12. Persistent Key-Value Store
Category: Trie-based coding problemYou are designing a persistent key-value store that serializes its state to a binary storage medium. Native serialization (e.g., JSON, pickle,...Input: Array
Output: Computed result
coding
Hard
Verified Question
#13
13. Shard Rebalancer
Category: String coding problemYou are implementing a shard management system for a distributed key-value store. Each shard is identified by a string and covers a contiguous range...Input: String
Output: Computed result
coding
Hard
Verified Question
#14
14. IP Address Iterator
Category: String coding problemEvery device on the public internet is identified by an IPv4 address written in dotted-decimal notation as
"A.B.C.D", where each octet is an...Input: StringOutput: Computed result
coding
Medium
Verified Question
#15
15. Version Support Finder
Category: Binary search coding problemA software company maintains a sorted list of version strings in ascending chronological order. A critical feature was introduced in one version, and...Input: List
Output: Computed result
coding
Medium
Verified Question
#16
16. Monster Battle Simulator
Category: String coding problemSimulate a deterministic, turn-based battle between two ordered teams of monsters. Execute the fight step by step and produce a chronological battle...Input: List
Output: Computed result
coding
Medium
Verified Question
#17
17. Distributed Tree Messaging
Category: Tree coding problemYou are implementing a message-passing protocol for a distributed system organized as a rooted n-ary tree. Each node represents a machine and...Input: List
Output: Printed output
coding
Hard
database
#1
1. [OA] Algorithm Complexity — Evaluate model performance metrics in SQL
OpenAI needs efficient ways to calculate performance metrics of its AI models across large datasets.
Problem statement: Given a table
Input: N/A
Output: "SELECT model_id, AVG(accuracy) AS average_accuracy FROM model_performance GROUP BY model_id ORDER BY average_accuracy DESC LIMIT 5;"
Explanation: This query calculates the average accuracy of each model and retrieves the top 5.Example 2:
Input: N/A
Output: "SELECT model_id, AVG(accuracy) AS average_accuracy FROM model_performance WHERE timestamp > '2023-01-01' GROUP BY model_id ORDER BY average_accuracy DESC LIMIT 5;"
Explanation: This further restricts to models launched after a specific date.Constraints:
-
Problem statement: Given a table
model_performance with columns model_id, accuracy, and timestamp, write a SQL query to find the top 5 models by average accuracy over time, ordered from highest to lowest average accuracy.Example 1:Input: N/A
Output: "SELECT model_id, AVG(accuracy) AS average_accuracy FROM model_performance GROUP BY model_id ORDER BY average_accuracy DESC LIMIT 5;"
Explanation: This query calculates the average accuracy of each model and retrieves the top 5.Example 2:
Input: N/A
Output: "SELECT model_id, AVG(accuracy) AS average_accuracy FROM model_performance WHERE timestamp > '2023-01-01' GROUP BY model_id ORDER BY average_accuracy DESC LIMIT 5;"
Explanation: This further restricts to models launched after a specific date.Constraints:
-
model_performance contains at least 1 and at most 100,000 rows.
coding
Hard
sliding window
#2
2. [OA] Sliding Window — Implement a text summarization algorithm for OpenAI's API
The ability to summarize large texts efficiently is crucial for OpenAI's API, allowing users to quickly digest information.
Problem statement: Given an input string
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Input: "OpenAI provides a platform for developers to build applications using AI. The company focuses on promoting and advancing artificial intelligence. Their tools are user-friendly and accessible."
Output: "OpenAI provides a platform for developers to build applications using AI. Their tools are user-friendly and accessible."
Explanation: The function extracts 2 key sentences from the input text for the summary.Example 2:
Input: "Artificial intelligence has numerous applications, including natural language processing and robotics. OpenAI is at the forefront of this technology, constantly innovating products that leverage AI."
Output: "OpenAI is at the forefront of this technology, constantly innovating products that leverage AI."Constraints:
-
- The number of sentences in
Problem statement: Given an input string
text representing a large text body, your task is to implement a function summarize_text(text: str) -> str that uses a sliding window approach to summarize the text by extracting key sentences while maintaining coherence.-
summarize_text returns a str representing the summarized text.Example 1:Input: "OpenAI provides a platform for developers to build applications using AI. The company focuses on promoting and advancing artificial intelligence. Their tools are user-friendly and accessible."
Output: "OpenAI provides a platform for developers to build applications using AI. Their tools are user-friendly and accessible."
Explanation: The function extracts 2 key sentences from the input text for the summary.Example 2:
Input: "Artificial intelligence has numerous applications, including natural language processing and robotics. OpenAI is at the forefront of this technology, constantly innovating products that leverage AI."
Output: "OpenAI is at the forefront of this technology, constantly innovating products that leverage AI."Constraints:
-
text consists of 1 to 10^6 characters.- The number of sentences in
text will not exceed 100.Related OpenAI Data Scientist interview prep
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