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Coding & Algorithms Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
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Showing 2191–2220 of 3276 results
- OracleMediumSoftware EngineerMaximum stock trading profit with at most two buy-and-sell transactions
A stock trading optimization problem: given daily prices, find the maximum profit using at most two buy-then-sell transactions while holding at most one share at a time. It tests reasoning about splitting the price history into non-overlapping trades and handling falling, flat or steadily rising prices.
Coding & AlgorithmsOther - OracleMediumSoftware EngineerMerge Accounts by Shared Identifiers
This problem tests graph traversal techniques (BFS/DFS) and Disjoint Set Union (DSU) to group connected entities based on shared attributes.
Coding & AlgorithmsOnsiteGraphDSUDFS - OracleMediumSoftware EngineerMinimize sum with halving operations
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Minimize sum with halving operations states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - OracleMediumSoftware EngineerMinimum number of rooms needed to hold overlapping meetings
A coding question that asks for the minimum number of rooms needed so that every meeting in an unsorted list of half-open time intervals can be held without overlap. It tests reasoning about overlapping intervals, the boundary rule for meetings that end and start at the same time, and an efficient solution for large inputs.
Coding & AlgorithmsOnsite - OracleEasySoftware EngineerProcess Tokens with Explicit Expiration Times
This problem tests your ability to manage temporal data using efficient data structures, specifically focusing on handling expiration logic and range-based queries.
Coding & AlgorithmsOnsiteHash MapHeapDesign - OracleMediumSoftware EngineerRearrange an Integer Array into Its Next Lexicographic Arrangement
A coding problem that asks you to rearrange an integer array into the next lexicographically greater arrangement of its values, wrapping around to ascending order when the array is already the largest. It tests reasoning about lexicographic order, repeated values and complexity analysis.
Coding & AlgorithmsTechnical Screen - OracleMediumSoftware EngineerRemove Even-Positioned Nodes from a Linked List
This problem tests your ability to manipulate singly linked list pointers in-place, specifically managing alternating node removals while maintaining correct connectivity.
Coding & AlgorithmsOnsiteLinked ListPointersAlgorithms - OracleMediumSoftware EngineerRepeatedly Delete Runs of k Adjacent Equal Characters from a String
Given a lowercase string and an integer k, repeatedly delete k adjacent equal characters, letting the remaining parts join and possibly form new runs, until no deletion is possible, then return what remains. It tests efficient simulation of cascading removals on strings of up to 100,000 characters.
Coding & AlgorithmsTechnical Screen - OracleEasySoftware EngineerReplace a Range of Nodes in a Linked List with Another Linked List
Given two singly linked lists and two indices i and j, replace nodes i through j of the first list with every node of the second list and return the new head. It tests careful pointer relinking, head and tail edge cases, and an empty replacement list.
Coding & AlgorithmsOnsite - OracleMediumSoftware EngineerReturn a valid course completion order
This question evaluates understanding of graph algorithms and dependency resolution, specifically skills in cycle detection and producing valid orderings of tasks.
Coding & AlgorithmsOnsite - OracleMediumBackend EngineerReturn the K Most Frequent Values with a Larger-Value Tie-Break
This problem tests proficiency with hash maps for frequency counting and custom sorting logic using priority queues or sorting algorithms.
Coding & AlgorithmsOnsiteHash MapSortingPriority Queue - OracleMediumSoftware EngineerShortest Subarray Whose Distinct-Value Sum Reaches a Target
Find the length of the shortest contiguous subarray of positive integers whose sum reaches a target when each distinct value is counted only once. A coding-screen problem that tests reasoning about contiguous ranges, bookkeeping for repeated values, and correct handling of the case where no subarray qualifies.
Coding & AlgorithmsOnsite - OracleEasySoftware EngineerSimulate a Least Recently Used Cache
This problem tests your ability to maintain data access recency and perform cache evictions in O(1) time complexity using a combination of a hash map and a doubly linked list.
Coding & AlgorithmsOnsiteData StructuresHash MapLinked List - OracleMediumSoftware EngineerSimulate an LFU cache that evicts the least-used key, breaking ties by recency
Implement and simulate a least-frequently-used cache with fixed capacity that evicts the key with the lowest use count, breaking ties by least recent use. It tests exact eviction semantics, treating updates and reads as uses, and supporting every get and put in constant average time.
Coding & AlgorithmsOther - OracleMediumSoftware EngineerSolve Five Coding Problems
This set tests proficiency across five key algorithmic domains: graph theory, array manipulation, numerical properties, cache design, and tree traversal.
Coding & AlgorithmsOnsiteGraphsLRU CacheRecursion - OracleMediumSoftware EngineerSolve three DSA problems: trie, window, intervals
This multi-part question evaluates proficiency with core data structures and algorithms — specifically trie-based string indexing and autocomplete design, sliding-window/prefix-sum optimization for maximizing a one-shot decrypted range, and interval merging — within the Coding & Algorithms domain, emphasizing practical implementation, complexity analysis and edge-case handling. It is commonly asked in technical interviews to assess the ability to design efficient data structures and linear-time algorithms, reason about time/space trade-offs and ordering constraints, and demonstrate both conceptual understanding and practical application through clear complexity analysis.
Coding & AlgorithmsOnsite - OracleMediumBackend EngineerSplit a String into Exactly Three Palindromes
Tests string partitioning, palindrome verification, and algorithmic optimization using dynamic programming or two pointers.
Coding & AlgorithmsOnsiteStringDynamic ProgrammingTwo Pointers - OracleMediumSoftware EngineerSum the Binary Numbers Spelled by Root-to-Leaf Paths in a 0/1 Tree
Given a binary tree of 0 and 1 bits in level-order form, return the sum of the binary numbers spelled by every root-to-leaf path, reading the root as the most significant bit. The problem tests tree traversal, carrying an accumulated value down each path, and parsing a level-order serialization correctly.
Coding & AlgorithmsTechnical Screen - OracleMediumSoftware EngineerTimestamped key-value store: return each key's value as of a query time
A coding question that processes set and get operations on a key-value store where each write carries a timestamp and each read asks for a key's value as of a given time. It tests per-key version history, finding the latest write at or before a query time, and handling many interleaved operations efficiently.
Coding & AlgorithmsOnsite - OscarEasySoftware EngineerFind Clients Outside Provider Coverage
This problem tests spatial data processing and efficient set operations to identify gaps in service coverage between clients and providers based on distance and specialty requirements.
Coding & AlgorithmsTechnical ScreenAlgorithmsSpatialSet Operations - OscarMediumSoftware EngineerSolve Morse and Network Access Tasks
This question evaluates string encoding/decoding and combinatorial parsing skills (Morse code conversion and ambiguous decoding) alongside spatial search and filtering competencies for proximity-based access checks, testing algorithmic reasoning, pattern recognition, backtracking possibilities, distance computation, and data-structure use.
Coding & AlgorithmsOnsite - OtherEasyData ScientistCheck if a numeric string is divisible by 8
Determine whether a very large non-negative integer given as a decimal string is divisible by 8 without converting the whole string to an integer. The key insight is that only the last three digits matter (since 1000 is a multiple of 8), giving an O(1) check; a streaming modular-remainder approach is the O(n) alternative.
Coding & AlgorithmsTechnical Screen - OtherMediumBackend EngineerCompare Strings With Deletions
This question evaluates string processing and algorithmic optimization skills, specifically handling simulated deletions (backspace behavior) and performing comparisons under a strict auxiliary space constraint.
Coding & AlgorithmsTechnical Screen - OtherMediumSoftware EngineerCompute total after discounting most expensive item
This question evaluates array manipulation and numeric computation skills—specifically identifying the maximum element, applying a percentage discount, and correctly handling fractional results and flooring—within the Coding & Algorithms domain.
Coding & AlgorithmsOnline Assessment - OtherEasySoftware EngineerCount Failing, Passing and Distinction Scores from Percentage Thresholds
Given an array of student exam scores as percentages, count how many students failed with under 50, passed with 50 to 80 inclusive, or passed with distinction above 80, and return the three counts in order. It tests careful handling of inclusive and exclusive boundaries and empty input.
Coding & AlgorithmsOnline Assessment - OtherMediumSoftware EngineerCount Grid Paths Without Three Consecutive Moves
Count monotone grid paths that use exact numbers of right and up moves without ever taking three identical moves in a row. Address empty and one-direction paths, return an exact count, and explain how the limits affect time and space costs.
Coding & AlgorithmsOnline Assessment - OtherEasySoftware EngineerFewest Days to Read a Book When Chapters Cannot Be Split Across Days
Given the reading time available on each day and the time each chapter of a book takes, find the fewest days needed to read every chapter in order when a chapter can never be split across days, or report that the book cannot be finished. It tests simulation with per-day capacity, ordering constraints, and impossible cases.
Coding & AlgorithmsOnline Assessment - OtherMediumSoftware EngineerFilter Logs by an Ordered Severity Threshold
Filter structured logs by an ordered minimum severity, preserving threshold-and-higher records while handling empty and unknown levels under an explicit contract.
Coding & AlgorithmsOnsite - OtherMediumData ScientistImplement KNN from scratch
This question evaluates understanding of the k-Nearest Neighbors algorithm, distance metrics (Euclidean and cosine), tie-breaking with class priors, weighted voting, complexity analysis, and scalability strategies, testing competencies in algorithm implementation, model behavior, and computational trade-offs.
Coding & AlgorithmsOnsite - OtherMediumMachine Learning EngineerImplement Linear Regression Training
This question evaluates understanding of linear regression, mean squared error loss, gradient computation, parameter updates, and proficiency with vectorized numerical operations used in batch gradient descent.
Coding & AlgorithmsOnsite
Oracle