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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
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Showing 301–330 of 3276 results
- AmazonMediumSoftware EngineerSolve three coding tasks: binary search, tree path, subarray
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Solve three coding tasks: binary search, tree path, subarray states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerSolve tree and DP problems
This pair of problems evaluates proficiency with tree data structures and traversal concepts (deepest shared ancestor) and with dynamic programming/state optimization on linear arrays (maximizing non-adjacent house values), assessing algorithmic reasoning, complexity awareness, and data-structure manipulation.
Coding & AlgorithmsTechnical Screen - AmazonMediumSoftware EngineerSolve two set and graph problems
This question evaluates proficiency in data-structure manipulation (set operations, mapping and deduplication), directed-graph modeling and traversal for reachability, and algorithmic time/space complexity analysis.
Coding & AlgorithmsOnsite - AmazonEasyData ScientistSolve two string DP/hash problems
This question set evaluates string-processing and algorithmic problem-solving skills, including encoding and transformation for unique representations and dynamic programming, memoization, and backtracking for enumerating all valid segmentations.
Coding & AlgorithmsTechnical Screen - AmazonMediumData ScientistSolve two-sum variants at scale
This question evaluates array and hashing algorithms, pair-sum reasoning including duplicate handling and lexicographic minimality, streaming and external-memory algorithm design, trade-offs in time/space complexity, and extension to three-sum with deduplication.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerSpreadsheet Formulas with Dependency Updates
Design a simplified in-memory spreadsheet supporting direct cell assignment, formula assignment (summation with potential duplicate cell references), and retrieval with dynamic dependency propagation.
Coding & AlgorithmsOnsitegraphdesignhash-table - AmazonMediumSoftware EngineerStack Whose Pop Removes the Most Frequent Value, Ties Broken by Recency
Phone screen coding problem: process push and pop operations on a stack in which every pop removes the value that currently occurs most often, breaking ties by the tied value closest to the top. It tests designing a data structure that tracks frequency and recency together efficiently.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerTrack Missing Package IDs from Out-of-Order Receipts
This problem tests the ability to track a range of sequential integers and identify gaps in a stream of incoming data using efficient data structures.
Coding & AlgorithmsTechnical ScreenArraysHash TablesData Structures - AmazonMediumSoftware EngineerTrack the Contiguous Package Frontier and Missing IDs
This problem tests your ability to manage sparse, out-of-order data using data structures like sets or priority queues and finding gaps within a contiguous range.
Coding & AlgorithmsTechnical ScreenData StructuresHashingArrays - AmazonEasySoftware EngineerUnify Stock-Trading Profit Variants
This problem tests state-space dynamic programming by unifying different stock trading constraints (transaction limits and per-transaction fees) into a single optimized state-transition model.
Coding & AlgorithmsTechnical ScreenDynamic ProgrammingState MachineOptimization - AmazonMediumSoftware EngineerValidate 9x9 grid in one pass
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Validate 9x9 grid in one pass states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnsite - AmazonEasySoftware EngineerValidate Properly Nested Brackets
Tests understanding of basic data structures—specifically stacks—to validate balanced and nested bracket sequences in linear time.
Coding & AlgorithmsTechnical Screenstackstringsdata-structures - AmazonMediumSoftware EngineerValidate a training courses catalog
This problem tests your ability to model prerequisites as a directed graph and detect circular dependencies using cycle detection algorithms (Kahn's or DFS).
Coding & AlgorithmsTechnical ScreenGraphTopological SortDFS - AmazonMediumSoftware EngineerVersioned Integer Array with Snapshots and Point-in-Time Reads
A coding problem about a fixed-length integer array that supports point updates, numbered snapshots of the whole array, and reads of any position as of an earlier snapshot, processed as a list of operations. It tests designing a versioned data structure that stays fast and memory-efficient when snapshots are frequent.
Coding & AlgorithmsOther - Ambience HealthcareMediumSoftware EngineerDesign a least-recently-used cache
Design a least-recently-used cache 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 - AmericanMediumSoftware EngineerCover the Most Points with an Axis-Aligned Rectangle of Bounded Perimeter
Maximize point coverage with an axis-aligned rectangle under a perimeter budget, including boundary points and repeated coordinates.
Coding & AlgorithmsOnline Assessment - AmericanMediumSoftware EngineerSpread Nine Stones Across a Three-by-Three Grid with Minimum Moves
Calculate the minimum number of orthogonal moves needed to distribute stones so that every cell in a 3x3 grid contains exactly one stone.
Coding & AlgorithmsOnline AssessmentBacktrackingRecursionMatrix - AmperityMediumSoftware EngineerRender Overlapping Rectangles on an ASCII Canvas
Render bordered and filled rectangles onto a fixed ASCII canvas, clipping safely and honoring input-order overwrites. Handle negative coordinates, fully hidden shapes, one-cell dimensions, trailing spaces, overlap behavior, and a canvas of up to one million cells.
Coding & AlgorithmsOnsite - AmplitudeMediumSoftware EngineerImplement Employee Validation and Snake
This question evaluates recursion, graph traversal and cycle-detection concepts for hierarchical employee validation alongside state management, event-driven input handling and collision detection for a grid-based Snake game.
Coding & AlgorithmsOnsite - AmplitudeMediumSoftware EngineerSwap kth-from-end node with head
This question evaluates a candidate's understanding of singly linked list pointer manipulation, in-place node swapping with O(1) extra memory, and handling of edge cases such as when the k-th node from the end is the head.
Coding & AlgorithmsTechnical Screen - Anchorage DigitalMediumSoftware EngineerDesign a dynamic leaderboard with rank queries
This question tests the ability to maintain a dynamic set of scores and efficiently query the rank of a user, requiring a balance between update complexity and retrieval time.
Coding & AlgorithmsTechnical ScreenData StructuresOrder StatisticsTrees - Anchorage DigitalMediumSoftware EngineerPrint the File System State
This problem tests your ability to recursively traverse a tree structure and format the output into a specific, ordered directory-style string representation.
Coding & AlgorithmsTechnical ScreenTrieRecursionTrees - AndurilMediumSoftware EngineerBuild a Dynamic Exact-Suffix Search Index
Design an in-memory index that supports dynamically inserting words and checking whether any previously inserted word ends with a given suffix in time proportional to the suffix length.
Coding & AlgorithmsOnsiteTrieStringData Structure Design - AndurilMediumSoftware EngineerEvaluate a Variadic Addition or Subtraction Expression
Implement a variadic prefix expression evaluator supporting addition and left-associative subtraction with support for nested expressions and error handling.
Coding & AlgorithmsOnsiteRecursionStackExpression Evaluation - AndurilMediumSoftware EngineerFind Heap Objects Not Referenced by the Stack
Implement a simplified mark-and-sweep sweep phase to identify unreferenced heap objects given a list of heap allocations and stack root pointers.
Coding & AlgorithmsTechnical Screenhash-tablememory-managementarrays - AndurilMediumSoftware EngineerFind Unreachable Objects in a Heap Graph
Implement a mark-phase reachability analysis for a heap graph starting from stack roots, returning unreachable heap addresses in their original order while handling cycles, self-references, and dangling pointers.
Coding & AlgorithmsTechnical Screengraphsbfs-dfshash-table - AndurilMediumSoftware EngineerMaximize Profit From Cutting Rods
This problem tests dynamic programming and optimization skills by requiring the calculation of the maximum profit obtainable from cutting a rod into integer-length pieces with given price values.
Coding & AlgorithmsTechnical ScreenDynamic ProgrammingOptimizationAlgorithms - AnsysMediumSoftware EngineerImplement Prefix Search and Node Removal
This question evaluates proficiency in string data structures and manipulation (prefix-search concepts including case-insensitive matching and regex-based normalization) as well as linked list pointer manipulation and in-place node removal.
Coding & AlgorithmsTechnical Screen - AnthropicMediumSoftware EngineerAccount Balance with Expiring Grants
Design a data structure that tracks time-limited credit grants, prioritizes consuming grants that expire earliest, and efficiently manages expired funds.
Coding & AlgorithmsOnsiteHeapGreedyDesign - AnthropicMediumSoftware EngineerApply bitwise tricks for performance
This question evaluates proficiency with bitwise operations, branchless programming, low-level performance optimizations, and microarchitectural reasoning about pipeline stalls, instruction-level parallelism, and cache behavior.
Coding & AlgorithmsOnsite
Amazon
Anthropic