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"
"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."
Implement firewall matching with CIDR rules
Implement a simple IPv4 firewall rule matcher. Problem You are given an ordered list of firewall rules. Each rule has: - an action: ALLOW or DENY - a ...
Debug round-robin, DashMap, and simple cache
You are given a service that routes requests to a list of nodes, each marked as either available or unavailable. The pickNode() function is intended t...
Compute binary tree diameter
Compute binary tree diameter Given the root of a binary tree, compute the tree's diameter defined as the maximum number of edges on any path between t...
Design LCA with flexible inputs and rule
Design LCA with flexible inputs and rule Design a function to find the lowest common manager of two employees in an organizational tree. Support two i...
Sort a string by custom order
Sort a string by custom order Given a priority string P of distinct characters and a text string S, reorder S so that all characters appearing in P co...
Assess HashMap vs ConcurrentHashMap
Assess HashMap vs ConcurrentHashMap Is Java's HashMap thread-safe? Explain why or why not. How does ConcurrentHashMap achieve thread safety and perfor...
Compare final, finally, finalize
Compare final, finally, finalize Compare Java's final keyword, the finally block, and the finalize() method. For each, explain purpose, typical use ca...
Implement a String Deque
Implement a double-ended queue (Deque) that stores strings. Your implementation must support the following operations: - addFirst(data): Insert data a...
Compute median of two sorted arrays
You are given two sorted arrays of integers nums1 and nums2. - nums1 has length m, nums2 has length n. - Both arrays are sorted in non-decreasing orde...
Find LCA in a N-ary tree via DFS
You are given the root of a rooted N-ary tree (each node can have zero or more children) and two distinct nodes p and q that belong to the tree. Desig...
Solve Two Grid Search Problems
Solve the following two coding problems. 1. Count disconnected land regions - You are given an m x n grid of characters where '1' represents land a...
Find shortest jumps in circular array
You are given a circular array arr of length n. From index i, you may jump exactly arr[i] steps either to the left or to the right (wrapping around th...
Fetch, group, and print paginated activities
Fetch, group, and print paginated activities Given a paginated API that returns (totalCount, activities[]) for a requested page, implement code that i...
Implement flat_map, redistribute wealth evenly
Implement flat_map, redistribute wealth evenly Implement std::flat_map in C++, including its iterator; explain design choices and add thorough test ca...
Perform matrix Candy Crush elimination
Question Implement a function that, given an m × n integer matrix representing colored blocks (same integers = same color), performs one round of "Can...
Implement custom iterator classes
Implement custom iterator classes In a blank coding environment (no IDE assistance, no autocomplete), implement an iterator abstraction entirely from ...
Solve weighted pick and product except self
Question LeetCode 528. Random Pick with Weight LeetCode 238. Product of Array Except Self https://leetcode.com/problems/random-pick-with-weight/descri...
Design test-run logging and query functions
Question Implement log(test_id, timestamp, status) to record a test run, where timestamps are strictly increasing across all test IDs. Implement get_m...
Find longest segment with dominant ends
Question Given an integer array nums, find and return the length of the longest contiguous subarray such that the first and last elements of the subar...
Count subarrays with ≥k identical pairs
Question LeetCode 2537. Count the Number of Good Subarrays – Given an integer array nums and an integer k, return the number of contiguous subarrays i...