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Software Engineer 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 1–30 of 354 results

  • AbridgeHardSoftware Engineer
    Expand a Nested Repeat-Count Encoded String

    From an Abridge online assessment: decode a string in which k[text] means the bracketed text repeated k times, with multi-digit counts, nested brackets and plain letters between encoded parts. It tests parsing nested structure correctly and building the expanded output efficiently.

    Coding & AlgorithmsOnline Assessment
  • AbridgeHardSoftware Engineer
    Run-Length Compress a Character List With Multi-Digit Counts

    From an Abridge online assessment: run-length compress a list of characters, writing each run of equal adjacent characters as the character followed by its length, with lengths of 10 or more split into separate digit characters. It tests careful run handling and the in-place, constant-space form of the problem.

    Coding & AlgorithmsOnline Assessment
  • AbridgeHardSoftware Engineer
    Sum of Integers Up to n Divisible by 3, 5, or 7

    From an Abridge online assessment: given a positive integer n, return the sum of all integers from 1 to n that are divisible by 3, 5 or 7, adding numbers such as 15 or 21 only once. It tests precise handling of overlapping divisibility conditions and inclusive range boundaries.

    Coding & AlgorithmsOnline Assessment
  • AirbnbMediumSoftware Engineer
    Implement Connect Four with win detection

    This question evaluates a candidate's ability to design efficient data structures and algorithms for real-time game state management, including win detection, API design, time/space complexity analysis, and handling edge cases such as full or out-of-range columns.

    Coding & AlgorithmsOnline Assessment
  • AirbnbHardSoftware Engineer
    Process a Timestamped Workspace Credit Ledger

    Design and implement an in-memory timestamped credit ledger that supports deposits, transfers, spending with delayed cashback rewards, account merges, balance queries, and spend rankings.

    Coding & AlgorithmsOnline AssessmentData StructuresDesignHeap
  • Akuna CapitalMediumSoftware Engineer
    Compute max profit across dated stock quotes

    This question evaluates a candidate's ability to reason about time-series and transaction-constrained optimization, including handling unsorted inputs, duplicate records, and constructing an explicit sequence of trades under ordering and no-short-selling constraints.

    Coding & AlgorithmsOnline Assessment
  • Akuna CapitalMediumSoftware Engineer
    Compute min operations to transform integers

    This question evaluates algorithmic problem-solving skills related to integer transformations and reasoning about sequences of allowed operations, focusing on optimizing the number of steps. It is commonly used in the Coding & Algorithms domain to assess practical application of algorithmic thinking and time-complexity analysis, testing efficiency reasoning rather than purely conceptual knowledge.

    Coding & AlgorithmsOnline Assessment
  • Akuna CapitalMediumSoftware Engineer
    Heapify an array into a max-heap

    This question evaluates understanding of heap data structures and the in-place bottom-up heapify algorithm for building a max-heap on a 0-indexed array, testing skills in array manipulation, heap invariants, and algorithmic reasoning.

    Coding & AlgorithmsOnline Assessment
  • Akuna CapitalMediumSoftware Engineer
    Solve swaps, graph paths, and movie DP

    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 swaps, graph paths, and movie DP states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsOnline Assessment
  • Akuna CapitalMediumSoftware Engineer
    Solve three C++ algorithmic tasks

    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 C++ algorithmic tasks states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.

    Coding & AlgorithmsOnline Assessment
  • Akuna CapitalMediumSoftware Engineer
    Trace code and find frequent character

    Trace code and find frequent character 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 & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Add One Source to Minimize Grid Inconvenience

    Minimize the worst inconvenience in a binary grid by adding one colored source. Movement is allowed in eight directions, and the solution must handle grids that begin with no source at all.

    Coding & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Build 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
  • AmazonHardSoftware Engineer
    Circular 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 Engineer
    Compute 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 Engineer
    Compute 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 Engineer
    Compute 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 Engineer
    Compute 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 Engineer
    Count Four-Neighbor Islands in a Binary Matrix

    Count four-neighbor islands in a binary matrix and consider the connectivity state needed when rows arrive as a stream.

    Coding & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Count partitions and equal-cost packages

    This question evaluates string-processing and combinatorial counting skills, including tracking distinct-character occurrences across contiguous partitions and using frequency-based pairing logic on arrays to form equal-cost packages.

    Coding & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Design faster delay-time computation

    This question evaluates a candidate's ability to design efficient array algorithms and appropriate data structures for nearest-smaller-element queries, assessing performance, correctness with duplicates, and scalability to large inputs.

    Coding & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Determine Rounds for Star Substring Threshold

    This question evaluates string-processing and algorithmic problem-solving skills, including handling incremental updates, counting substrings impacted by character replacements, and performance-aware simulation.

    Coding & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Drone Circular Route — Minimum Total Travel Cost

    This problem tests your ability to solve a variation of the Traveling Salesman Problem using bitmask dynamic programming to optimize route costs in a small, weighted graph.

    Coding & AlgorithmsOnline AssessmentDynamic ProgrammingBitmaskingGraph Theory
  • AmazonHardSoftware Engineer
    Fewest Severity Inversions When Interleaving Two Patch Queues

    Merge two severity-labeled patch queues into one install order that keeps each queue's internal order, and return the minimum number of severity inversions over every valid merge. Tests DP over two sequences and efficient counting with letters as priorities.

    Coding & AlgorithmsOnline Assessmentdynamic-programmingstringsinversions
  • AmazonHardSoftware Engineer
    Find Longest Activatable Server Streak

    This problem tests your ability to use the sliding window technique to find the longest contiguous subarray that satisfies a specific count-based constraint.

    Coding & AlgorithmsOnline AssessmentSliding WindowTwo PointersArray
  • AmazonHardSoftware Engineer
    Find a Maximum-Sum Window in a Sparse Array

    This problem tests the ability to optimize sliding window calculations for extremely large arrays by leveraging compressed data structures (run-length encoding) rather than materializing the full array.

    Coding & AlgorithmsOnline AssessmentSliding WindowArraysOptimization
  • AmazonMediumSoftware Engineer
    Find a valid dependency order

    This question evaluates understanding of directed graphs, dependency resolution and cycle detection, and the ability to reason about valid ordering constraints within a graph representation.

    Coding & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Find longest segment with dominant ends

    This question evaluates algorithmic problem-solving with arrays and complexity-aware design, testing skills in efficient subarray identification, boundary reasoning, and performance analysis within the Coding & Algorithms domain.

    Coding & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Find longest segment with endpoints > interior

    This question evaluates algorithmic design and array-processing skills, specifically reasoning about subarray endpoint vs interior relationships, range comparisons, and designing solutions with subquadratic time and space complexity.

    Coding & AlgorithmsOnline Assessment
  • AmazonMediumSoftware Engineer
    Find minimum days to deliver all orders

    This question evaluates algorithm design and combinatorial optimization skills, focusing on scheduling and load-balancing under per-center capacity constraints and frequency-based counting.

    Coding & AlgorithmsOnline Assessment