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.
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"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
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"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
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"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Reorder Search Results for Provider Diversity
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Design a Recency-Eviction Cache
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Implement an Alternating Tic-Tac-Toe Game
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Calculate Circular Route Query Distance
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Design an IPv4 Address Iterator
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Evaluate Arithmetic Expressions
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Find Maximum Island Perimeter
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Find Earliest Fully Connected Time
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Optimize trade PnL table updates
This question evaluates understanding of incremental aggregation and state management, including handling overlapping predicates, caching expensive or...
Implement tag matcher and filesystem
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Implement LRU cache and prime products array
You are given two separate coding tasks. Task 1: Implement an LRU cache Implement an in-memory cache with a fixed capacity that evicts the least recen...
Implement Multi-Level In-Memory Services
Implement the following independent multi-level in-memory service simulations. In an interview, you may receive one scenario and unlock the levels seq...
Write SQL revenue and anomaly queries
You are given two tables. Table: transactions | Column | Type | Description | |---|---|---| | transaction_id | int | Unique identifier for each transa...
Find Maximum Chain Activations
You are given n devices, where each device is represented as [x, y, r]. Device i is located at coordinates (x, y) and can directly activate device j i...
Solve checksum and dependency debugging tasks
This question evaluates skills in string processing, modular arithmetic-based checksum computation and mapping, plus debugging of feature enablement l...
Reverse Linked List Groups
This question evaluates linked list manipulation, pointer/reference management, in-place iterative algorithms, and the ability to enforce O(1) extra s...
Replace Delimited Tokens in a String
This question evaluates string parsing, token recognition, and dictionary lookup competencies for robust text replacement, including handling malforme...
Split Markdown Into Header-Aware Chunks
Implement a function that splits a Markdown document into ordered chunks, where each chunk must not exceed a given size limit. A Markdown header is a ...