20 questions · from 6 interviews
Nielsen interview questions
Every question candidates reported from their Nielsen interviews, most frequently asked first. Each links to the write-up it came from, so you can see the round and how it went.
Nielsen coding and DSA questions
- 01
Count Distinct Quadruplets Summing to Target
Given an array arr and a target value, find the count of distinct sets of {a,b,c,d} indices such that arr[a] + arr[b] + arr[c] + arr[d] = target. The indices a, b, c, d must be distinct.
- 02
Max Marked Indices with 2*arr[i] <= arr[j]
Given an array arr, pick pairs of indices {i, j} for which 2arr[i] <= arr[j]. Each index can only be part of one pair. Return the maximum number of such marked indices (total count of i and j chosen) in the array.
- 03
Next Greater Element I
The next greater element of some element x in an array is the first element to its right that is strictly greater than x. You are given two 0-indexed integer arrays nums1 and nums2 of unique elements, where nums1 is a subset of nums2. Find all the next…
Easy · From Nielsen | MTS - 2 | Interview Questions
- 04
Binary Tree Maximum Path Sum
A path in a binary tree is a sequence of nodes where each pair of adjacent nodes in the sequence has an edge connecting them. A node can only appear in the sequence at most once. Note that the path does not need to pass through the root. The path sum of a…
Hard · From Nielsen | MTS - 2 | Interview Questions
- 05
Permutations
Given an array nums of distinct integers, return all the possible permutations. You can return the answer in any order. (LeetCode Problem: Permutations)
Medium · From Nielsen MTS-2 (Full-Stack Developer)
Nielsen system design questions
- 01
Train Booking System Design
Design a train booking system with core functionalities: Search between stations Availability of seats Booking Cancellation and Refund (bonus) Focus on API design, schema based on datastore, and clean code following OOP and SOLID principles.
From Nielsen Backend Engineer MTS4/SMTS Interview Experience | May 2026
- 02
Splitwise LLD
Design a low-level system for a Splitwise-like application.
- 03
Ads Click Impression System Design
Design a system for tracking ad clicks and impressions.
- 04
Design a Movie Ticket Booking System (BookMyShow)
I was asked to design a movie ticket booking system similar to BookMyShow. This involved discussing basic requirements, outlining a high-level flow, identifying required entities and their relationships, and drawing an HLD of the overall system including…
- 05
Design a Task Management System
Design a Task Management System that allows users to create, assign, update, and track tasks. The system should support multiple users, task priorities, due dates, and status tracking. Users should be able to categorize tasks, add comments, and receive…
- 06
High-Level Design for an E-commerce App (Myntra-like)
Design the high-level architecture for a large-scale e-commerce application similar to Myntra, considering scalability, availability, core functionalities (e.g., product catalog, user management, order processing), and relevant technologies.
Hard · From Nielsen MTS-2 (Full-Stack Developer)
- 07
Low-Level Design for Add to Cart Functionality
Design the low-level architecture for the 'Add to Cart' functionality, covering both front-end (UI/UX, state management, API integration) and back-end (API endpoints, database interactions, business logic, error handling) implementations.
Medium · From Nielsen MTS-2 (Full-Stack Developer)
Nielsen other questions
- 01
React Memory Game LLD
Create a Memory Game in React. Given rows and columns, generate an m x n matrix of cards. Each card has a value. On click, a card reveals its value. If two revealed cards have matching values, remove them from the list. Otherwise, flip them back (hide their…
Medium · From Nilesen - MTS3 (UI)
- 02
Internal Working of Hashmap
Discuss the internal implementation details of a hashmap, including its data structure, collision resolution strategies, and performance characteristics.
- 03
Multithreaded Collections
Explain how collections work and behave in multithreaded environments, including potential issues like race conditions and common solutions for thread-safe collection access.
- 04
React Hooks and Photo Gallery App Use Cases
Discuss React Hooks, their principles, and demonstrate their practical application and benefits within the context of building a photo gallery application.
- 05
UI/UX Optimization Techniques
Explain and discuss methods like skeleton loading, adaptive loading, and asset optimization to improve the user experience and performance of a web application.
- 06
Multithreading and Kafka Internals
Discuss advanced concepts in multithreading and explain the internal architecture and working principles of Apache Kafka, including topics, partitions, producers, and consumers.
- 07
SQL Partitioning Scenario
Solve a SQL scenario-based problem requiring the use of database partitioning for performance optimization or data management, explaining the rationale and implementation.
Medium · From Nielsen MTS-2 (Full-Stack Developer)
- 08
SQL LEFT JOIN Query
Write a SQL query demonstrating the use of a LEFT JOIN operation between two or more tables, explaining its behavior and use cases.
Easy · From Nielsen MTS-2 (Full-Stack Developer)
Nielsen interview questions FAQ
What questions are asked in Nielsen interviews?
Candidates reported 20 distinct questions across 6 Nielsen interviews. 5 coding and DSA questions, 7 system design questions, 8 other questions.
How difficult are Nielsen interview questions?
Of the questions candidates rated, 25% were easy, 50% medium and 25% hard.