Coding & Algorithms Interview Questions

Practice 3,469 real Coding & Algorithms interview questions for 2026. Covers companies like Meta, Amazon, Google, Uber, and Microsoft. Real questions from actual interviews with detailed solutions — ideal for focused interview preparation. Coding & Algorithms interview questions are the single most common technical gate for software engineering roles and are used to evaluate problem framing, algorithm selection, complexity trade-offs, correctness, edge-case reasoning, and clear communication under time pressure. Expect this category to appear in early technical screens and repeatedly across onsite loops at companies that weight it heavily (notably Meta, Google, and Amazon). Interviews will test arrays and strings, trees and graphs, dynamic programming, hashing and two‑pointer techniques, and the candidate’s ability to test and optimize code in a shared editor. Prepare with timed mock interviews, practice in the same editor you’ll use live, and build a progressive schedule that moves from fundamentals to medium/hard problems; typical candidates invest several weeks to a few months of focused practice depending on seniority and target company.

3.5k Questions 368 Companies08.11.2026
Showing 20 results
Role
CloudKitchens logo
CloudKitchens
Medium
Software Engineer

Design a menu manager with enums

Design and implement a console-based restaurant menu management program. Requirements: ( 1) There are exactly three fixed item categories represented ...

Coding & Algorithms
7
0
86 people solved
Sep 6, 2025
LinkedIn logo
LinkedIn
Medium
Software Engineer

Differentiate Java final, finalize, finally

Differentiate Java's final, finalize, and finally. Define what final means for variables, methods, and classes and give examples; explain what finaliz...

Coding & Algorithms
8
0
75 people solved
Sep 6, 2025
Qube Research & Technologies logo
Qube Research & Technologies
Medium
Software Engineer

Implement a type-erased function wrapper

Implement a minimal std::function-like callable wrapper in C++ using type erasure via inheritance and a virtual call. Define a template Function<R(Arg...

Coding & Algorithms
8
0
87 people solved
Sep 6, 2025
Zoox logo
Zoox
Easy
Data Scientist

Choose fastest way to transfer 2 TB

You need to transfer a 2 TB dataset to someone located in San Francisco as fast as possible. - What transfer method(s) would you choose and why? - St...

Coding & Algorithms
9
0
124 people solved
Nov 13, 2025
Rippling logo
Rippling
Hard
Software Engineer AI Locked

Build a Flexible Expense Rules Engine

This question evaluates designing extensible rule engines, predicate composition, data modeling for expense- and trip-level aggregation, and reasoning...

Coding & Algorithms
17
0
125 people solved
Feb 27, 2026
Nuro logo
Nuro
Medium
Software Engineer Locked

Reveal a Minesweeper Board

Implement the reveal operation for a Minesweeper board. Correctly handle mine clicks, numbered cells, and recursive empty-region expansion across all ...

Coding & Algorithms
1
0
10 people solved
Jun 17, 2026
Bytedance logo
Bytedance
Medium
Software Engineer Locked

Shortest Path in a Grid with Limited Obstacle Removal

This question evaluates a candidate's ability to extend classic breadth-first search into a state-augmented shortest-path problem, where the state inc...

Coding & Algorithms
0
0
4 people solved
Jun 17, 2026
Expedia logo
Expedia
Hard
Software EngineerSenior+ Locked

Maximum Sum Skyline

This question tests algorithmic problem-solving with array optimization under a mountain (single-peak) shape constraint. It evaluates practical applic...

Coding & Algorithms
0
0
8 people solved
Jun 17, 2026
Rippling logo
Rippling
Easy
Software Engineer

Implement an article voting tracker

Coding: Article Voting Tracker Design and implement a data structure to track users’ votes (upvote/downvote) on articles. Operations Implement functio...

Coding & Algorithms
24
0
438 people solved
Dec 5, 2025
Google logo
Google
Medium
Machine Learning Engineer Locked

Implement substring search and weighted sampling

This question evaluates algorithm design and analysis skills across string processing (efficient substring search) and randomized/data-structure techn...

Coding & Algorithms
13
0
114 people solved
Mar 30, 2026
Anthropic logo
Anthropic
Medium
Software Engineer

Generate outputs for images and pipelines

You are given m input images and n processing pipelines. - Each pipeline is an ordered list of k operations (e.g., resize, rotate, crop, blur, color t...

Coding & Algorithms
115
0
1247 people solved
Nov 10, 2025
Google logo
Google
Hard
Software Engineer

Apply Range Overwrite Queries

You are given an integer array nums of length n and a list of range-assignment queries. Each query is a tuple (left, right, value), where left and rig...

Coding & Algorithms
22
1
232 people solved
Feb 25, 2026
Coinbase logo
Coinbase
Medium
Software Engineer Locked

Compute Total Manual Distance

This question evaluates array processing, state simulation, and algorithmic reasoning for deterministic stepwise processes, including handling unsorte...

Coding & Algorithms
5
0
54 people solved
Mar 29, 2026
Oracle logo
Oracle
Medium
Software Engineer

Implement an LRU cache

Design and implement a data structure for a Least Recently Used (LRU) cache with a fixed capacity. The cache must support: - get(key): return the valu...

Coding & Algorithms
8
0
72 people solved
Jan 26, 2026
Pinduoduo logo
Pinduoduo
Medium
Software EngineerSenior+

Traverse a Matrix in Spiral Order

Traverse a Matrix in Spiral Order Problem Given an m x n matrix, return all elements in clockwise spiral order. Begin at the top-left corner, move rig...

Coding & Algorithms
0
0
8 people solved
May 4, 2026
OpenAI logo
OpenAI
Medium
Android Engineer Locked

Build a Compose Rating Card

This question evaluates proficiency in Android UI development with Kotlin and Jetpack Compose, emphasizing custom composable design (a stateless star-...

Coding & Algorithms
43
0
289 people solved
May 3, 2026
Uber logo
Uber
Medium
Software Engineer

Solve BFS and grid tasks

The coding rounds included several algorithmic problems: 1. Threshold search with binary search: You are given floors 1..n and an API canOperate(floor...

Coding & Algorithms
12
0
91 people solved
Feb 22, 2026
Goldman Sachs logo
Goldman Sachs
Hard
Machine Learning Engineer

Complete decision tree and gradient descent functions

You are given partially implemented code and must complete key functions. Implement the missing parts with correct logic and reasonable efficiency. Ta...

Coding & Algorithms
13
0
98 people solved
Oct 10, 2025
Snowflake logo
Snowflake
Hard
Software Engineer Locked

Implement a JSON Parser

This question tests practical knowledge of parsing theory, including lexical analysis and recursive-descent parsing applied to a well-defined grammar....

Coding & Algorithms
0
0
6 people solved
Jun 15, 2026
Bytedance logo
Bytedance
Hard
Backend EngineerNew Grad Locked

SQL: Students Above Average and Passing Every Subject

This question tests practical SQL skills, specifically the use of aggregate functions and conditional filtering across grouped data. It evaluates the ...

Coding & Algorithms
0
0
4 people solved
Jun 15, 2026

Frequently Asked Questions

How difficult are Coding & Algorithms interview questions?
Difficulty spans a wide range: from quick easy warm-ups to multi-stage hard problems that require advanced data structures or algorithmic proofs. Most companies place a majority of live coding rounds at the medium level, with occasional hard questions used to distinguish senior candidates. Interviewers evaluate problem framing, algorithm choice, time/space complexity, clean implementation, and thoughtful testing under time pressure. Expect more conceptual depth at Google, more consistent medium-to-hard screens at Meta, and Amazon to mix coding with leadership signals. Leveling depends on role and seniority: entry-level focuses on fundamentals; senior roles emphasize design, optimizations, and tradeoffs.
Where does Coding & Algorithms appear in a typical interview loop, and which companies weight it most heavily?
Coding & Algorithms is usually the first technical hurdle: it appears in phone/online screens, followed by one or more onsite or virtual coding rounds during the loop. Typical sequences are a technical screen, two to three in-loop coding sessions, then system design or behavioral rounds. Companies that weight this category heavily include Google, Meta, and Amazon, where coding performance often determines whether you progress. Candidates commonly concentrate practice for weeks or months beforehand; most targeting large tech firms prepare intensively for 6–12 weeks, while some spend 3–6 months for deeper mastery or level changes.
How long should I prepare and how should I structure that preparation?
Plan focused, progressive practice over a realistic timeline. A practical structure is an 8–12 week block: weeks 1–2 solidify fundamentals and language fluency; weeks 3–6 target core patterns (arrays, trees, graphs, DP) with timed problem sessions and pattern tagging; weeks 7–9 emphasize mock interviews, end-to-end problem solving, and optimization tradeoffs; final weeks simulate real loops with full-length sessions and targeted weak-point drills. Candidates with less experience may extend to 12–16 weeks. Regularly review mistakes, practice communicating solutions aloud, and include at least one weekly mock interview with peer or coach feedback.
What key subtopics and patterns should I master for Coding & Algorithms interviews?
Master a consistent set of patterns and their variations: arrays and strings (two pointers, sliding window), hash maps and frequency counts, sorting and binary search, recursion and backtracking, dynamic programming, trees and traversals, graphs (BFS/DFS, shortest paths, union-find), heaps and priority queues, and greedy algorithms. Also practice complexity analysis, space-time tradeoffs, and writing bug-resistant code with tests. For higher levels, focus on amortized analysis, advanced graph algorithms, segment trees or Fenwick trees, and system-aware optimizations. Interviewers value reusable problem templates and the ability to generalize patterns to new prompts.
What are standout tips and common pitfalls to avoid in Coding & Algorithms interviews?
Start by clarifying requirements and constraints, then outline your approach before coding. Write a correct, readable baseline solution first, then iterate to improve complexity while narrating tradeoffs. Test with simple and edge cases, and handle nulls, off-by-one, and empty inputs explicitly. Communicate continuously; silence looks like confusion. Avoid premature optimization, overcomplicating solutions, or ignoring interviewer hints. Time management matters: if stuck, discuss alternate approaches and code a partial solution. Finally, practice mock interviews to reduce anxiety and build the habit of clear, structured explanations under pressure.

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