Oracle interview questions

Shortest Path in a Grid with Obstacles Elimination

Find the minimum number of steps from the top-left to bottom-right in a 4-directional binary grid if you may remove up to k obstacles; treat…

Companies: Oracle, Amazon, Cisco, D. E. Shaw +2

Array · Breadth-First Search · Matrix

Last reported Apr 2025

What are you trying to improve most (professionally)

Companies: Oracle, Meta, Moveworks, Rubrik

Last reported Apr 2025

Add two decimal strings e.g. '123.45' + '236.7'

Like LeetCode 415. Add Strings, but with the additional consideration that there can be decimals with varying precision.

Companies: Oracle

Last reported Jan 2025

Design a Temperature Monitoring System

Design a temperature monitoring system that displays current and historical temperature data across a 10 million km² area with sensors placed every 10 km². Users…

Companies: Oracle, Amazon, Uber

Last reported Jan 2025

Design an AI tutoring platform with RAG based Q&A for assignments and coursework

Design an AI-powered tutoring platform that uses Retrieval-Augmented Generation (RAG) to help students get answers to questions about their assignments and coursework. The…

Companies: Oracle

Last reported Jan 2025

What is the difference between encoder and decoder architectures of neural networks? Describe the transformer architecture in detail.

Companies: Oracle

Last reported Jan 2025

What would you do to avoid underfitting and what would you do to avoid overfitting?

Companies: Oracle

Last reported Jan 2025

Design a User Data Deletion System

Design a system that allows users to request the deletion of all their data, handling large-scale multi-step deletion processes and notifying users upon completion.

Companies: Oracle

Last reported Aug 2024

Design a notification system

Async processing with durable queues, per-channel isolation, retries/DLQ, at-least-once + idempotency, outbox, priorities.

Companies: Oracle, Airbnb, Amazon, Autodesk +24

async-processing · idempotency · outbox-pattern · queues

Last reported May 2024

4Sum

Find all unique quadruplets of distinct elements in an integer array whose values sum to a given target. Results must avoid duplicates (order irrelevant); with…

Companies: Oracle

Array · Sorting · Two Pointers

Accounts Merge

Given lists of accounts where each account has a name and emails, merge accounts that share any email by grouping connected emails (e.g., via union-find…

Companies: Oracle, Airbnb, Bloomberg, Meta +1

Array · Breadth-First Search · Depth-First Search · Hash Table

Cheapest Flights Within K Stops

Find the minimum-cost route from src to dst in a directed weighted graph with the constraint of at most k stops (i.e., a bound on…

Companies: Oracle, Flipkart, Illumio, Meta +1

Breadth-First Search · Depth-First Search · Dynamic Programming · Graph Theory

Decode String

Decode a string containing nested repeat patterns of the form k[encoded_string], expanding each bracketed segment k times (k may be multi-digit) possibly with multiple nesting…

Companies: Oracle, Bloomberg, Coupang, Google +4

Recursion · Stack · String

Design a large data migration to the cloud

Moving a changing dataset across a limited link: resumable bulk copy, change capture, independent integrity checks, and a fenced cutover.

Companies: Oracle, Google

bandwidth-management · change-data-capture · cutover · integrity-verification

Design Dropbox or Google Drive

Large file transfers with small metadata transactions: resumable uploads, offline conflicts, reliable change feeds, and shared subtrees whose permissions change as files move.

Companies: Oracle, Amazon, Apple, Autodesk +17

access-control · change-data-capture · conflict-resolution · data-versioning

Longest Substring Without Repeating Characters

Find the length of the longest contiguous substring that contains no repeated characters. This is a classic sliding-window / two-pointer problem where you track seen…

Companies: Oracle, Amazon, Apple, Autodesk +12

Hash Table · Sliding Window · String

Maximum Subarray

Find the contiguous subarray within an integer array that yields the maximum possible sum and return that sum. This is typically solved in O(n) with…

Companies: Oracle, Amazon, Google, LinkedIn +5

Array · Divide and Conquer · Dynamic Programming

Remove All Adjacent Duplicates in String II

Given a string s and integer k, repeatedly remove any run of k equal adjacent characters until no more removals are possible and return the…

Companies: Oracle, Amazon, Apple, Meta +2

Stack · String

Search in Rotated Sorted Array

Given an ascending array of distinct integers that has been rotated at an unknown pivot, return the index of a target value (or -1 if…

Companies: Oracle, Amazon, Expedia, Google +3

Array · Binary Search

Valid Parenthesis String

Determine whether a string containing '(', ')', and '*' (where '*' can represent '(', ')', or empty) can be assigned so the parentheses are balanced…

Companies: Oracle, Apple, Microsoft

Bracket Sequences · Dynamic Programming · Greedy · Stack