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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.
- 9403
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 91–120 of 3276 results
- AmazonMediumSoftware EngineerAnswer two coding questions (SQL and DP)
This problem tests SQL data aggregation skills with NULL handling and algorithmic proficiency in dynamic programming to count palindromic subsequences in a string.
Coding & AlgorithmsTechnical ScreenSQLDynamic ProgrammingAggregation - AmazonMediumSoftware EngineerBuild a BFS Web Crawler
This question evaluates understanding of breadth-first traversal, URL normalization, domain scoping, duplicate detection, and retry/error handling, measuring algorithmic design and robustness in networked code.
Coding & AlgorithmsTechnical Screen - AmazonHardSoftware EngineerBuild a Searchable Sentence Index
This problem tests your ability to design an in-memory inverted index for text retrieval, requiring efficient tokenization, case-insensitive mapping, and dynamic updates to a collection of sentences.
Coding & AlgorithmsOnsiteHash MapsInverted IndexData Structures - AmazonHardSoftware EngineerBuild an LRU Cache with a Hash Map and Linked List
This problem tests your ability to design a cache with O(1) time complexity for both get and put operations by combining a hash map with a doubly linked list.
Coding & AlgorithmsHR ScreenHash MapLinked ListDesign - AmazonMediumSoftware EngineerBuild the Largest Available Sequence
This problem tests your ability to use a greedy approach combined with a frequency map to construct the lexicographically largest sequence under specific constraints.
Coding & AlgorithmsOnline AssessmentGreedyPriority QueueFrequency Map - AmazonMediumSoftware EngineerCaesar Cipher with Translation-Table Optimization
This question tests string manipulation, modular arithmetic, and the ability to optimize performance by trading space for time using a precomputed lookup table.
Coding & AlgorithmsTechnical ScreenStringsOptimizationAlgorithms - AmazonMediumData ScientistCalculate 7-Day Rolling Average for Energy Consumption
This question evaluates programming fluency in numerical data processing and algorithmic implementation for computing moving averages and handling edge cases in time-series sequences, and it applies to Data Scientist roles while falling under the Coding & Algorithms category.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerCalculate Circular Route Query Distance
This question evaluates a candidate's ability to reason about circular arrays, distance computations, and query-efficient algorithms, assessing concepts such as modular indexing and cumulative distances.
Coding & AlgorithmsTechnical Screen - AmazonEasySoftware EngineerCheck a Palindrome While Ignoring Case and Punctuation
Tests string manipulation and two-pointer traversal techniques to verify if a string is a palindrome while ignoring non-alphanumeric characters and case.
Coding & AlgorithmsTechnical ScreenStringsTwo PointersEasy - AmazonMediumApplied ScientistCheck if adding edge creates cycle in digraph
This question evaluates understanding of graph algorithms, reachability, and algorithmic complexity by determining whether adding a directed edge would introduce a cycle in an otherwise acyclic directed graph.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerCheck path in N-ary tree
This question evaluates understanding of tree traversal and sequence matching in N-ary trees, including handling non-unique node values and maintaining traversal state across branches.
Coding & AlgorithmsOnsite - AmazonHardSoftware EngineerCircular Drone Hub Delivery Route
This question evaluates a candidate's ability to work with circular array structures and prefix sums to compute shortest distances on a ring topology. It tests practical coding skill in efficiently handling wraparound arithmetic and cumulative sums, a common pattern in algorithm interviews assessing array manipulation and optimization under scale constraints.
Coding & AlgorithmsOnline Assessment - AmazonMediumSoftware EngineerCompute Edit Distance
Tests dynamic programming and string manipulation by calculating the minimum number of single-character edits (insertions, deletions, substitutions) needed to transform one string into another.
Coding & AlgorithmsTechnical ScreenDynamic ProgrammingStringsAlgorithms - AmazonMediumSoftware EngineerCompute Latencies and Search Grid Path
This question evaluates parsing and processing of timestamped event logs to compute message latencies and implementation of constrained grid path search, testing competencies in file I/O, record alignment/matching, time-delta computation, graph traversal, and stateful backtracking.
Coding & AlgorithmsTechnical Screen - AmazonMediumData ScientistCompute array modes with ties and no-mode rule
This question evaluates algorithm design and data-structure skills—frequency counting, hashing, and handling edge cases such as ties and a no-mode rule—within the coding and algorithms domain for data scientist roles.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerCompute delay times in priority array
This question evaluates algorithmic efficiency in array processing, specifically reasoning about nearest-smaller relationships and the use of auxiliary structures to achieve subquadratic performance.
Coding & AlgorithmsOnline Assessment - AmazonMediumSoftware EngineerCompute fruit spoilage time in a grid
This question evaluates a candidate's understanding of graph traversal concepts, grid-based state propagation, and reachability analysis in time-evolving systems.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerCompute maximum distinct-product pickup days
This question evaluates a candidate's understanding of greedy and resource-allocation strategies along with combinatorial reasoning to maximize operations under discrete constraints.
Coding & AlgorithmsOnline Assessment - AmazonEasySoftware EngineerCompute minimal operations and optimal server pairing
This two-part question evaluates array manipulation and optimization skills—specifically range-update minimization to enforce a nondecreasing sequence and greedy pairing/matching to maximize summed primary resources—testing algorithm design, complexity reasoning, and constraint handling.
Coding & AlgorithmsOnline Assessment - AmazonMediumSoftware EngineerCompute optimal locker placement with obstacles
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Compute optimal locker placement with obstacles states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerCompute peak parking lot occupancy intervals
This question evaluates a candidate's competency in temporal interval reasoning, event-stream processing, and handling incomplete or unsorted logs to determine peak concurrent occupancy.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerCompute product excluding index without division
This question evaluates array-manipulation and algorithmic problem-solving skills, focusing on computing a product-for-each-index using prefix and postfix accumulation concepts while reasoning about edge cases such as zeros, negative numbers, and integer overflow.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerCompute reachability and minimal-time same-type scheduling
This prompt evaluates integer reachability and invariant reasoning via repeated additive transformations (testing number-theoretic reachability and state-space analysis) alongside resource-aware scheduling and grouping logic for minimizing completion time under type and memory constraints, and it falls under the Coding & Algorithms domain.
Coding & AlgorithmsOnline Assessment - AmazonMediumSoftware EngineerCompute shortest path with obstacles
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Compute shortest path with obstacles states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerCompute the Median After Each Stream Insertion
This problem tests your ability to maintain dynamic statistics in a data stream using efficient data structures to achieve logarithmic insertion and constant-time retrieval.
Coding & AlgorithmsOnsiteHeapsData StreamsSorting - AmazonEasySoftware EngineerCompute the Minimum Number of Meeting Rooms
This problem tests your ability to manage overlapping time intervals efficiently, requiring an understanding of sorting or priority queues to track resource utilization.
Coding & AlgorithmsTechnical ScreenSortingIntervalsGreedy - AmazonMediumSoftware EngineerCompute total revenue from greedy VM rentals
This problem tests your ability to use greedy strategies combined with efficient data structures to manage resource allocation and optimize revenue based on priority-based demand.
Coding & AlgorithmsTechnical ScreenGreedyData StructuresHeap - AmazonMediumSoftware EngineerCompute tree diameter
This question evaluates understanding of binary tree algorithms, recursion versus iterative traversal strategies, and competence in algorithmic analysis including time and space complexity and handling deep-recursion stack overflow when computing a tree's diameter.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerCount Connected Components in an Undirected Graph
This question tests the ability to traverse an undirected graph using graph search algorithms to identify and count disjoint subgraphs.
Coding & AlgorithmsTechnical ScreenGraphsBFSDFS - AmazonMediumSoftware EngineerCount Customers Who Visited on Multiple Dates
Tests data manipulation, hash set/map aggregation, and date deduplication to identify users with repeat visits across distinct calendar days.
Coding & AlgorithmsTechnical ScreenHash TableCountingString
Amazon