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."
"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 two sorted arrays in-place
This question evaluates array-manipulation and in-place algorithm skills, including understanding of sorted-data merging, index/pointer management, an...
Find Top Hashtags
You are given two arrays of length n: - tweets[i]: the content of the i-th tweet as a string - timestamps[i]: the publish time of the i-th tweet as an...
Find Longest Increasing Continuous Subarray
Solve the longest increasing contiguous subarray problem in one pass. Includes Python code, edge cases, complexity, and a follow-up for returning the ...
Count Closed Islands
This question evaluates a candidate's understanding of grid-based connectivity and the ability to detect enclosed regions, testing skills in graph rep...
Merge two sorted linked lists
This question evaluates proficiency with linked list data structures, pointer manipulation, in-place merging concepts, and algorithmic efficiency with...
Solve grid shortest-path and tree DP
This question pair evaluates proficiency in fundamental algorithmic techniques: finding shortest paths in a grid via breadth-first search and applying...
Write SQL and merge linked lists
The technical interview included two coding-style tasks: a SQL analytics query and merging two sorted linked lists. Constraints & Assumptions - For SQ...
Maximize 1D deliveries within distance and minimize total distance
This question evaluates combinatorial optimization and constrained matching skills, focusing on reasoning about distance-based pairings, lexicographic...
Implement Cache and Count Components
You are asked to solve two independent coding problems in this session, each followed by a short discussion. This mirrors a 60-minute Amazon SDE codin...
Implement scaled dot-product attention
Task In this interview you are asked to hand-write the forward pass of attention from the mathematical formula (no need to run code). Implement single...
Maximum-Product Simple Path in a Complete Directed Graph
You are given a complete directed graph with n nodes labeled 0 through n - 1. For every ordered pair of distinct nodes (i, j), there is a directed edg...
Find two numbers that sum to target
Problem You are given an integer array nums (length n) and an integer target. Return the indices (i, j) such that: - i != j - nums[i] + nums[j] == tar...
Count unique Morse-code word transformations
Given an array of lowercase strings words. Each letter 'a' to 'z' has a corresponding Morse code string (standard 26-letter mapping). A word’s transfo...
Find shortest subarray with ≥k distinct integers
This question evaluates understanding of array algorithms, handling of distinct-element counting, and the ability to design time- and space-efficient ...
Count Enclosed Islands in a Grid
This question evaluates grid traversal and graph concepts such as connected-component detection, boundary-condition reasoning, and algorithmic time/sp...
Validate normalized palindromes with variants
Implement a function isNormalizedPalindrome(s) that returns true if s reads the same forward and backward after removing non‑alphanumeric characters a...
Count Distinct Island Shapes in a Binary Grid
You are given an m x n binary grid grid, where grid[i][j] is either 0 (water) or 1 (land). An island is a maximal group of 1-cells connected 4-directi...
Implement nested object path lookup
This question evaluates parsing and traversal of nested maps and arrays, robust error handling for missing keys and out-of-bounds indices, and reasoni...
Find Most Frequent Values
Given an integer array nums and an integer k, return the k distinct values that occur most frequently in nums. The result may be returned in any order...
Count Special Index Pairs
Given an integer array nums of length n, count the number of index pairs (i, j) such that: - 0 <= i < j < n - nums[i] * nums[j] is even - j - i is odd...