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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 61–90 of 1080 results
- 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 - 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 - 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 - 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 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 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 - AmazonMediumSoftware EngineerMedian of a Data Stream
Design a data structure that continuously receives a stream of integers and efficiently supports retrieving the current running median, handling potential integer overflow during the median calculation.
Coding & AlgorithmsOnsiteHeapData StreamDesign - AmazonMediumSoftware EngineerMerge overlapping and adjacent ranges
This question evaluates a candidate's understanding of interval merging and range manipulation, including handling overlapping and adjacent ranges, edge cases like single-point gaps and extreme values, and the ability to analyze time and space complexity.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerMessage Rate Limiter
Design an in-memory message rate limiter that allows or denies messages based on whether a given time window has elapsed since their last accepted occurrence.
Coding & AlgorithmsOnsiteHash MapDesignRate Limiter - AmazonHardSoftware EngineerMinimize Replacements So Equal Product Values Are Contiguous
This problem tests your ability to optimize data transformations by identifying contiguous blocks of identical values, modeled as a shortest-path or dynamic programming problem on a compressed representation of the array.
Coding & AlgorithmsOnsiteGreedyDynamic ProgrammingData Structures - AmazonMediumSoftware EngineerMinimum Moves for a Squirrel to Carry Every Nut to a Tree One at a Time
A squirrel on an obstacle-free grid must carry every nut to a tree, holding at most one nut at a time and moving one cell per step. The task asks for the minimum total number of moves over all delivery orders, testing reasoning about grid distances and how the order of deliveries affects the total.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerOrder Dependent Tasks and Identify Work to Rerun
Return any valid dependency order, detect cycles, and identify transitive reruns with a complete topological and reachability solution and order-independent validation.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerReplace Delimited Tokens in a String
This problem tests string manipulation, hash map lookups, and edge-case handling when parsing nested or malformed delimiters within a template string.
Coding & AlgorithmsOnsiteStringsHash MapParsing - AmazonMediumSoftware EngineerSolve LeetCode string and list problems
This set of problems evaluates proficiency in string manipulation, priority-queue/heap usage and greedy strategies, and linked-list operations including pointer management and cloning, reflecting core data structure and algorithm competencies.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerSolve Nearby Inventory and Word Segmentation Tasks
Implement two independent tasks: identify stocked centers close enough to a graph destination and return any exact dictionary segmentation of a string. Handle disconnected routes, duplicate edges, missing inventory, repeated suffix work, and large inputs while explaining complexity.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerSolve Rotting Oranges and Bus Walk Reachability
This question evaluates graph and grid traversal skills, state modeling over time, and constrained reachability combining free transit edges with Manhattan-distance walking.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerSolve Shipping and Bundle-Cost Problems
This problem tests your ability to determine the minimum capacity required to complete tasks within a deadline and optimize the cost of purchasing items grouped in bundles.
Coding & AlgorithmsOnsiteBinary SearchDynamic ProgrammingOptimization - AmazonMediumSoftware EngineerSolve Union-Find, Graph, and Stream Problems
This question evaluates understanding of disjoint-set (union-find) operations, directed graph processing including cycle detection and ordering, contiguous subarray sum reasoning, and online streaming/anagram detection techniques, emphasizing data structures and algorithmic problem-solving.
Coding & AlgorithmsOnsite - AmazonMediumSoftware EngineerSolve sliding-window and heap problems
This question evaluates algorithm design and data structure proficiency, focusing on sliding-window techniques for fixed-length subarray aggregates and heap- or hashmap-based approaches for maintaining medians in a real-time integer stream, along with considerations for concurrent execution.
Coding & AlgorithmsOnsite - 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 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 - 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
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