Intern Coding & Algorithms Interview Questions
Intern coding rounds are where fundamentals win. These coding and algorithms questions were reported from internship interviews, so they cluster around the topics interns actually face: arrays and strings, hash maps, two pointers, stacks and queues, recursion, and the occasional easy graph or tree traversal. The difficulty band is mostly easy-to-medium, and interviewers care as much about clear communication and a working solution as they do about the perfect optimization. If you're prepping for a software engineering internship, this is the focused set to drill — real questions at the real difficulty, most with a step-by-step solution so you can check your reasoning.
"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."
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"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."
Streaming Equivalence of Two Trade Feeds with Per-Company Ordering
A market-data system receives trade events from two independent feeds. Each event is a pair (company, trade_id) identifying one trade for one company....
Validate Bracket Sequence
This question evaluates proficiency with stack data structures, string parsing and matching logic, and the ability to reason about algorithmic time an...
Reverse Words While Preserving Spaces
Implement a C++ function that reverses the order of words in a string. Assume a word is any maximal sequence of non-space characters, and the input co...
Count Same-Day Registered Posters
You are given two tables: `text users - user_id: unique identifier for a user - registered_at: timestamp when the user registered posts - post_id: uni...
Analyze sales with groupby
You are given three pandas DataFrames representing a food delivery marketplace: - orders(order_id, product_id, quantity, unit_price, status) - product...
Simulate sticky load balancer with shutdown
Problem Implement a simulator for a load balancer that routes long-lived WebSocket connections across m backend servers. You receive a sequence of tex...
Simulate 2048 and pack board into uint64
Problem: 2048 move simulation + board compression You are implementing part of the 2048 game on a fixed 4×4 grid. Part A — Simulate a move Given a 4×4...
Find pairs with the minimum absolute difference
Given an integer array (not necessarily sorted), find the minimum absolute difference between any two distinct elements. Return all pairs of values th...
Construct connected crop layout and safe paths
This question evaluates constructive grid design and graph-based pathfinding skills, specifically the ability to produce connected labeled regions tha...
Print all odd numbers from an integer list
This question evaluates proficiency with array/list manipulation, parity checking, and handling edge cases such as negative values and integers outsid...
Reconstruct a binary tree from traversals
This question evaluates understanding of binary tree traversal properties, data structure manipulation, and algorithmic complexity involved in reconst...
Maximize sum without choosing adjacent elements
This question evaluates a candidate's understanding of array-based optimization and dynamic programming concepts for computing a maximum sum under non...
Match people to questions using tags and priorities
This question evaluates competencies in bipartite matching and combinatorial optimization, along with practical data-structure design for scalable tag...
Find median of two sorted arrays
You are given two sorted arrays of integers nums1 and nums2 in non-decreasing order. Let the lengths be m = nums1.length and n = nums2.length. Either ...
Implement Univariate Linear Regression with Ordinary Least Squares
Implement univariate (simple) linear regression fitted in batch with the ordinary least squares (OLS) closed-form solution. You must implement the for...
Find kth missing integer and redundant operations
You are given two independent coding tasks. Task 1: K-th missing number You are given an integer array nums (not necessarily sorted) containing distin...
Find top-5 most similar rows across datasets
You are given two datasets with the same feature columns: - source (rows you want to match): - source_id (STRING/INT) - f1...fk (NUMERIC; may cont...
Implement Cache and Key-Value Store
The interview report mentions coding tasks similar to the following: 1. Bounded cache Implement a cache with a fixed capacity. Support: - get(ke...
Solve Grid and Counting Problems
A software engineering intern phone screen included two coding tasks: 1. Count islands in a grid Given an m x n grid of characters where '1' re...