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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 211–240 of 3276 results
- AmazonHardSoftware EngineerImplement a Half-Open Interval Range Module
This problem tests proficiency with balanced binary search trees or interval management techniques to efficiently track and manipulate sets of half-open intervals.
Coding & AlgorithmsTechnical ScreenIntervalsBinary SearchData Structures - AmazonMediumSoftware EngineerImplement a Min-Priority Queue Without a Library Heap
Tests implementation of a binary min-heap from scratch, including array-based representation, sift-up, and sift-down operations, without relying on built-in priority queue libraries.
Coding & AlgorithmsOnsiteHeapData StructuresDesign - AmazonMediumSoftware EngineerImplement a formatted shell script output
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Implement a formatted shell script output states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - AmazonMediumData ScientistImplement a high-throughput web crawler safely
This question evaluates competency in concurrent systems, scalable data ingestion, and algorithmic design for a high-throughput web crawler, covering URL normalization, deduplication, per-host rate limiting, fault-tolerant checkpointing, and bounded-memory queueing.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerImplement a robust shell CLI
This question evaluates proficiency in POSIX-compliant shell scripting, including positional argument parsing and validation, ISO 8601 UTC timestamp generation, file metadata extraction for license determination, construction of user@hostname, error handling and exit-code semantics, and handling of non-ASCII file paths.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerImplement ad matching and delivery routing
Implement ad matching and delivery routing evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsTechnical Screen - AmazonMediumData ScientistImplement and Analyze 'Merge k Sorted Lists' Algorithm
This question evaluates algorithm design skills and complexity analysis for merging multiple sorted sequences, measuring proficiency with appropriate data structures, time-space trade-offs, and correctness reasoning.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerImplement and Analyze an LRU Query Cache
Implement a fixed-capacity least-recently-used cache for integer query results with expected constant-time get and put operations. Refresh recency on hits and updates, evict the correct key on overflow, and handle misses and duplicate puts precisely.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerImplement basic calculator
This question evaluates skill in parsing and evaluating arithmetic expressions with integer operands and the operators +, -, *, and /, focusing on operator precedence and evaluation order within the Coding & Algorithms domain.
Coding & AlgorithmsOnline Assessment - AmazonMediumApplied ScientistImplement binary search lower/upper bounds
Implement lower_bound and upper_bound on a non-decreasing sorted array using iterative binary search in O(log n) time and O(1) space. This Amazon ML engineer screen tests precise boundary handling, loop-invariant reasoning, and edge cases like duplicates, empty arrays, and out-of-range targets.
Coding & AlgorithmsTechnical Screen - AmazonMediumApplied ScientistImplement decoder-only GPT-style transformer
This question evaluates implementation-level mastery of transformer architectures, including multi-head masked self-attention, position-wise feed-forward networks, residual connections, and precise tensor-shape reasoning for a decoder-only language model, within the Coding & Algorithms domain of deep learning and neural network engineering.
Coding & AlgorithmsOnsite - AmazonMediumApplied ScientistImplement integer division without using division
This question evaluates proficiency in implementing low-level integer arithmetic and algorithmic optimization, including correct handling of overflow and edge cases within 32-bit signed integer constraints.
Coding & AlgorithmsOnsite - AmazonMediumApplied ScientistImplement inventory allocation with backorders
Implement inventory allocation with backorders evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - AmazonMediumData ScientistImplement list overlap and dense-ranked word frequencies
This question evaluates a data scientist's ability to implement efficient multiset intersection and streaming top-k word-frequency computations, covering duplicate-aware counting, dense-ranking, Unicode handling, and strict time/space constraints.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerImplement robust debounce and throttle in JavaScript
This question evaluates a developer's ability to implement debounce and throttle utilities in JavaScript, testing competencies in asynchronous timing, timer management, cancellation/flush semantics, error propagation, and handling edge cases such as rapid bursts, timer drift, and re-entrancy.
Coding & AlgorithmsTechnical Screen - AmazonMediumData ScientistImplement streaming k-way merge with constraints
This question evaluates competence in streaming algorithms and resource-constrained algorithm design, specifically implementing a k-way merge over blocking, potentially unbounded integer iterators while preserving stable duplicates and reasoning about time and O(k) space complexity.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerImplement tree left/right views via BFS and DFS
This question evaluates understanding of binary tree traversal techniques and algorithmic reasoning for producing per-depth left and right views, assessing competencies in data structures, traversal ordering, and correctness across edge cases.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerImplement two array-cost minimization algorithms
This question evaluates algorithm design, data structure selection, and complexity analysis by requiring implementations for minimizing total merge cost and for removing a contiguous block to minimize the sum of adjacent absolute differences.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerInventory Allocation by Bid Priority
Implement a tiered inventory allocation system that distributes limited stock among buyer bids based on price tiers and round-robin priority rules.
Coding & AlgorithmsOnline AssessmentSimulationSortingGreedy - AmazonMediumSoftware EngineerJukebox That Plays the Most-Requested Song First
Design a request queue where each play takes the song with the most pending requests, with ties going to the most recent request. Tests keeping frequency and recency together so both operations run in O(1).
Coding & AlgorithmsOnsitedesignhash-mapstack - AmazonMediumSoftware EngineerJustify choosing JavaScript for interviews
This question evaluates a candidate's ability to articulate programming language trade-offs, understand language-specific runtime behaviors (types, hoisting, closures), and justify tool choice for front-end coding tasks within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerKth Largest Perfect Binary Subtree
This problem tests tree traversal techniques, the ability to validate binary tree properties recursively, and the use of selection algorithms to find order statistics.
Coding & AlgorithmsOnsiteTreesRecursionSorting - AmazonMediumSoftware EngineerLeaf Domain Cumulative Scores
This problem tests your ability to model hierarchical data using tree traversal and string manipulation to aggregate cumulative metrics across nested domains.
Coding & AlgorithmsOnsiteHash MapString ManipulationTree Traversal - AmazonHardSoftware EngineerLowest Common Ancestor in a Binary Search Tree
Tests finding the lowest common ancestor of two values in a Binary Search Tree represented as a level-order serialized list, accounting for self-ancestorship and missing-node edge cases.
Coding & AlgorithmsTechnical ScreenBinary Search TreeTreeBreadth-First Search - AmazonMediumSoftware EngineerMax total of k consecutive bags over disjoint valued segments, modulo 1e9+7
Disjoint segments [l, r, v] give every bag from position l to r the value v, and all other bags in an endless row are empty. Find the largest total over k consecutive bags, returned modulo 1,000,000,007, when k and positions reach 10^9, testing window sums over sparse ranges that cut through segments.
Coding & AlgorithmsOnline Assessment - AmazonHardSoftware EngineerMaximize Money in K Consecutive Bags
This problem tests your ability to efficiently manage interval operations and sliding window logic on a sparse coordinate system.
Coding & AlgorithmsTechnical ScreenSliding WindowSortingTwo Pointers - AmazonMediumSoftware EngineerMaximize Value Under a Budget
This problem tests your ability to solve a variation of the 0/1 Knapsack problem where items must be selected to maximize total value without exceeding a specific budget constraint.
Coding & AlgorithmsTechnical ScreenDynamic ProgrammingOptimizationAlgorithms - AmazonMediumSoftware EngineerMaximize capacity with primary-backup pairing
This problem tests your ability to optimize resource pairing using greedy strategies or sorting to maximize total capacity under specific pair-wise constraints.
Coding & AlgorithmsOnline AssessmentGreedySortingOptimization - AmazonMediumSoftware EngineerMaximize credits with limited skips
This question evaluates algorithm design and optimization skills in resource allocation under constraints, focusing on decision-making to maximize credits when turn-taking and limited skips affect processing.
Coding & AlgorithmsOnline Assessment - AmazonHardSoftware EngineerMaximize memory capacity with primary-backup servers
This question evaluates algorithmic reasoning in constrained pairings and resource allocation, focusing on maximizing aggregate memory under pairwise feasibility constraints while managing large input sizes.
Coding & AlgorithmsOnline Assessment
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