Coding & Algorithms Interview Questions
Practice 3,429 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.
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"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."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"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."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"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."
Merge Weekly Time Intervals
Implement merge_weekly_intervals(intervals). Each interval is [start_day, start_time, end_day, end_time]. Days are Mon, Tue, Wed, Thu, Fri, Sat, or Su...
Process Calendar Events with Deletion, Pagination, and Overlap Queries
Process Calendar Events with Deletion, Pagination, and Overlap Queries Process operations against an in-memory calendar. Every event has a unique name...
Count Overlapping Rectangle Updates on a Grid
Count Overlapping Rectangle Updates on a Grid Implement range_add_counts(n, rectangles). Start with an n x n matrix of zeroes. Each rectangle is repre...
Longest Substring Without Repeated Characters
Problem Implement longest_unique_substring(s). Return the longest contiguous substring of s that contains no repeated character. If several substrings...
Validate a Bijective Substitution Cipher
Validate a Bijective Substitution Cipher Given a plaintext string and an encoded string of equal length, determine whether one consistent one-to-one c...
Distribute Money Fairly Under Recipient Caps
Distribute Money Fairly Under Recipient Caps Problem Implement distribute(amount, recipients). amount is a pool of nonnegative integer minor currency ...
Calculate Tax from Progressive Brackets
Calculate Tax from Progressive Brackets Problem Implement calculateProgressiveTax(income, upperBounds, ratesBps) -> tax. income is a nonnegative integ...
Generate Function Profiling Events from Stack Samples
Generate Function Profiling Events from Stack Samples You receive timestamped call-stack samples in increasing timestamp order. Each sample is (timest...
Find the Single Value in a Sorted Array of Pairs
Find the Single Value in a Sorted Array of Pairs Problem Implement singleNonDuplicate(values) -> value. values is sorted in nondecreasing order. Exact...
Query an Indexed In-Memory Numeric Table
Query an Indexed In-Memory Numeric Table Problem Implement queryIndexedRows(rows, queries) -> answers for one immutable in-memory table containing onl...
Analyze Overlap in Closed Intervals
Implement closed_interval_overlap(intervals, query_points). Each interval [start, end] is closed, so it contains both endpoints. Return [[maximum_over...
Maximum L1 Distance Between Equal-Length Subarrays
Problem Implement max_l1_subarray_distance(a, b) for two nonempty integer arrays. Choose one nonempty contiguous subarray from a and one nonempty cont...
Find the Longest Subarray with at Most Two Distinct Values
Find the Longest Subarray with at Most Two Distinct Values Given an array of integers, return the length of the longest contiguous subarray containing...
Maintain Price Levels For A Single-Symbol Order Book
Review a single-symbol order book implementation prompt with insert, modify, cancel, and price-level lookup callbacks. The interview topic focuses on ...
Find Company Tickers Mentioned in a News Headline
Find Company Tickers Mentioned in a News Headline Problem Implement findMentionedTickers(companyNames, tickers, headline). companyNames[i] maps to tic...
Solve a Jigsaw Puzzle
You are given a collection of jigsaw puzzle pieces. Each piece has four edges — top, right, bottom, and left — and a helper function match(edgeA, edge...
Find and Count Maximum-Score Grid Paths
Find the maximum-scoring path from a fixed top-row cell to the last row of a grid using diagonal, downward, and limited two-row jump moves. Return the...
Enumerate 4x4 Tic-Tac-Toe Games
You are given an empty $4 \times 4$ board. Two players, X and O, alternate turns with X moving first. A player wins as soon as they place three of the...
Infection Spread Simulation with Death Threshold
This question evaluates a candidate's ability to implement grid-based simulation with multi-state cellular automaton logic, testing practical applicat...
Process Operations for an In-Memory Key-Value Store
Process Operations for an In-Memory Key-Value Store Implement an in-memory key-value store that supports adding or replacing a value, deleting a key, ...