Software Engineer Coding & Algorithms Interview Questions
Practice 2,306 real Coding & Algorithms interview questions for Software Engineer roles. From companies including Meta, Amazon, Google, Uber, Microsoft.
"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"
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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."
"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."
Design playlist with add/remove/shuffle
Music Playlist Data Structure Design an in-memory Playlist data structure that supports the following operations on a set of songs: - add(songId): Add...
Implement a thread-safe high-concurrency LRU cache
Problem Design and implement an in-memory LRU (Least Recently Used) cache that supports concurrent access. Basic requirements Implement a cache with f...
Merge collinear overlapping 2D segments
You are given a collection of 2D line segments. Each segment may be represented either as: - two endpoints (x1, y1) and (x2, y2), or - a polyline with...
Validate hiring request under role constraints
Problem You are building a simple HR assignment validator for a platform with companies, employees, and job roles. When the system receives a request ...
Check if one string is a subsequence of another
Given two strings s and t, determine whether s is a subsequence of t. A subsequence keeps relative order but does not require contiguous characters. I...
Serialize and deserialize a binary tree
Problem Design two functions to serialize and deserialize a binary tree. - Serialize: convert a binary tree into a single string. - Deserialize: recon...
Evaluate ACL rules for IP and CIDR
Problem You are implementing an IPv4 access-control list (ACL). The ACL contains ordered rules; each rule has: - action: either ALLOW or DENY - cidr: ...
Compute minimax grid path and network delay
Problem (two related shortest-path tasks) Part 1 — Minimize the maximum value along a grid path ("minimax" path) You are given an m x n integer grid H...
Dedupe titles in per-shelf viewport
You are rendering a streaming app home page. - The home page consists of shelves displayed from top to bottom. - Each shelf contains a list of titleId...
Implement array and tree traversal tasks
You are interviewing for a storage/infra-leaning role. Solve the following coding tasks and be ready to discuss time/space complexity and edge cases. ...
Solve matrix groups and recipe inventory
Problem 1: Find the smallest 3×3 group in a matrix You are given an m × n 2D integer array grid. - Partition the grid into non-overlapping 3×3 blocks,...
Design an in-memory filesystem and circular queue
Part A — Design an in-memory hierarchical file system. Requirements: - Support operations: ls(path), mkdir(path), createFile(path, content), appendToF...
Compute max team size with a core interval
You are given n employees’ working-time intervals, where employee i works during the inclusive interval [startTime[i], endTime[i]]. You want to form a...
Compute total after discounting most expensive item
Problem You are given: - An array prices of length n, where prices[i] is the price of the i-th item. - An integer discountPercent (0 to 100). A promot...
Solve four algorithmic problems
Solve the following coding tasks. For each, describe your approach, complexity, and handle edge cases. 1) Make parentheses string valid with minimal d...
Answer k-step ancestor queries in a rooted tree
You are given a rooted tree encoded as a parent array par[1..n] where: - Nodes are labeled 1..n. - par[i] is the parent of node i. - Exactly one node ...
Implement a Contiguous Memory Manager
You are asked to implement a contiguous memory manager for an array of n memory cells indexed from 0 to n - 1, where all cells are initially free. Sup...
Solve interval merging and histogram area
The coding round included two algorithm problems: 1. Merge overlapping intervals: Given a list of closed intervals [[start1, end1], [start2, end2], .....
Compare common data structures and uses
Compare common data structures and select appropriate ones for specific tasks. For arrays, linked lists, stacks, queues, hash tables, binary search tr...
Design a duplicate-file removal algorithm
Your filesystem contains millions of photos. Duplicates are strictly byte-identical files (no ML/CV similarity). Design an algorithm to detect and del...