40 questions · from 7 interviews · 1 asked more than once
Payu interview questions
Every question candidates reported from their Payu interviews, most frequently asked first. Each links to the write-up it came from, so you can see the round and how it went.
Payu coding and DSA questions
- 01
Two Sum Problem
Two sum problem.
Easy · Asked 2 times · From PayU Interview Experience | Software Engineer (SDE 2) | Selected
- 02
Frequency of an Element in a Sorted Array
Given a sorted array, count the occurrences of a target element k. Example: arr = [3, 5, 5, 5, 6, 9, 10], k = 5 → Output: 3
- 03
Minimum Jumps to Reach the End
You are given an array where each element represents the maximum jump length from that position. Find the minimum number of jumps to reach the end. Example: jump = [2, 1, 1, 3, 4] → Output: 3
- 04
Detect Cycle in a Linked List
Detect cycle in a linked list.
Easy · From PayU Interview Experience | Software Engineer (SDE 2) | Selected
- 05
Design Generic User Schema in SQL
Design a generic user schema in SQL.
Easy · From PayU Interview Experience | Software Engineer (SDE 2) | Selected
- 06
Reverse a Singly Linked List
Explained pointer reversal approach and implemented it.
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 07
Implement Binary Search
Walked through divide-and-conquer technique with code.
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 08
Merge Two Sorted Linked Lists
Described merging logic and pointer movement in sorted order.
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 09
Increasing Triplet Subsequence
The interviewer presented a problem where I needed to determine if there exists a triplet of indices (i, j, k) such that i
Medium · From PayU Worst Interview Experience | SSE | Bangalore | Awaiting
- 10
Maximum Number of Vowels in a Substring of Given Length
I was asked to find the maximum number of vowel letters in any substring of a given length. I solved this question optimally using a sliding window approach on the first attempt. When asked about time and space complexity, I stated O(n), but the interviewer…
Medium · From PayU Worst Interview Experience | SSE | Bangalore | Awaiting
- 11
Segregate Zeroes to End Inplace
Segregate all zeroes towards the end of the array using inplace operation. An extra array cannot be used. Input: [0, -7, 2, 11, 0, 0, 0, 13, 12, 0] Output: [-7, 2, 11, 13, 12, 0, 0, 0, 0, 0]
Medium · From PayU | SDE [Backend Java] | Gurugram | Oct 2023 [Reject]
- 12
Flatten Nested List and Calculate Weighted Sum
Flatten the nested list and return the calculated output. The calculation seems to imply a weighted sum based on nesting level. Input: [5, [6, 7, [8], 4]] Output Example: 5 1 + (6 + 7 + 83 + 4) 2 = ?
Medium · From PayU | SDE [Backend Java] | Gurugram | Oct 2023 [Reject]
- 13
Next Greater Number with Same Digits
Find the next greater number with the same set of digits. Examples: 123456 - 123465 54321 - -1
Medium · From PayU | SDE [Backend Java] | Gurugram | Oct 2023 [Reject]
- 14
Meeting Rooms III
The problem asks to determine which meeting room is used the most, given a list of meetings with start and end times, and a number of available rooms. When a room becomes free, it should be used for the next waiting meeting. If multiple rooms become free at…
From PayU Interview Experience | Gurgaon | Senior Software Engineer
- 15
Subdomain Visit Count
A website domain 'discuss.leetcode.com' consists of various subdomains. At the top level, we have 'com', at the next level, 'leetcode.com', and at the lowest level, 'discuss.leetcode.com'. When we visit a domain like 'discuss.leetcode.com', we also implicitly…
From PayU Interview Experience | Gurgaon | Senior Software Engineer
- 16
Binary Tree Right Side View
Given the root of a binary tree, imagine yourself standing on the right side of it, return the values of the nodes you can see ordered from top to bottom.
From PayU Interview Experience | Gurgaon | Senior Software Engineer
- 17
Container With Most Water
Given n non-negative integers a1, a2, ..., an where each represents a point at coordinate (i, ai) . n vertical lines are drawn such that the two endpoints of line i are at (i, ai) and (i, 0) . Find two lines, which, together with the x-axis, form a container,…
From PayU Interview Experience | Gurgaon | Senior Software Engineer
Payu system design questions
- 01
High Level Design of Instagram
High level system design of Instagram, covering functional and non-functional requirements, actors, schema design, data ingestion, user feed generation, handling celebrity posts, push vs pull models, ranking, scaling, rate‑limiting, and media storage.
Easy · From PayU Interview Experience | Software Engineer (SDE 2) | Selected
- 02
Design a Transaction Processing System
I was asked to design a transaction processing system with the following components: A → Web Service Layer Handles incoming requests and communicates with customers. B → Credit/Debit Banking Service Responsible for processing credit and debit transactions…
From PayU Interview Experience – Senior Software Engineer (Bangalore)
- 03
Frontend App with Polling Strategy
Scenario: Initiate a transaction → Bank confirms asynchronously - Solution: Used polling mechanism (no code required; conceptual discussion)
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 04
Cache Invalidation After New Deployments
Ensuring users see the latest version post-deploy (e.g., service workers, versioning)
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 05
JWT Token Handling
How to store, clean, and implement protected routes
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 06
Token/Payload Encryption
Preventing interception by API/network attackers
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 07
Job Scheduler for Loan Assessments System Design
Design a job scheduler to automate the process of running loan assessments for 1 million users on certain dates of a month at PayU. The system needs to fulfill the following requirements: 1. The business team should be able to configure the frequency/dates of…
Hard · From PayU | SDE [Backend Java] | Gurugram | Oct 2023 [Reject]
Payu other questions
- 01
Kafka Idempotency Support
Does Kafka support idempotency?
From PayU Interview Experience | Software Engineer (SDE 2) | Selected
- 02
Kafka Ordering Guarantee
Does Kafka guarantee ordering of events?
From PayU Interview Experience | Software Engineer (SDE 2) | Selected
- 03
API Design for Personalized GET Endpoint
Design a GET API fetching users' data, consumed by millions of clients, where the response varies per client and clients may request alterations in their response. How would you cater to this?
From PayU Interview Experience | Software Engineer (SDE 2) | Selected
- 04
super keyword in Inheritance
Explained its role in accessing parent class members.
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 05
Improving Design with Abstraction
Shared examples of how abstraction leads to clean, scalable code.
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 06
Garbage Collection & Memory Leaks in Java
Covered JVM’s automatic memory management and causes of leaks.
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 07
Checked vs. Unchecked Exceptions
Explained with real examples.
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 08
React App Performance Optimization
Strategies for faster initial loads and build optimizations
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 09
CORS Error Handling
Explained CORS, fixes, and IP whitelisting
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 10
Cookies vs Sessions vs Local Storage
Use-cases, lifetimes, and security considerations
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 11
Authentication vs Authorization
Differences with practical frontend examples
From 💼 PayU Interview Experiences – Intern + Backend + Frontend (Selected ✅)
- 12
Browser URL to Page Load Process
Explain in detail the entire process and underlying technologies involved when a user types a URL (e.g., www.google.com) into a web browser and presses Enter, leading to the display of the web page.
From PayU Interview Experience | Gurgaon | Senior Software Engineer
- 13
SOLID Principles
Discuss the five SOLID principles of object-oriented design (Single Responsibility, Open/Closed, Liskov Substitution, Interface Segregation, Dependency Inversion). Explain each principle with a brief description and provide examples of how they are applied in…
From PayU Interview Experience | Gurgaon | Senior Software Engineer
- 14
Memory Leak Concepts
Explain what a memory leak is in the context of programming, how it occurs, and describe common scenarios or patterns that lead to memory leaks. Discuss strategies and tools for preventing, detecting, and debugging memory leaks in applications.
From PayU Interview Experience | Gurgaon | Senior Software Engineer
- 15
Multithreading Concepts
Discuss fundamental concepts related to multithreading, including threads, processes, concurrency, and parallelism. Explain common challenges such as race conditions, deadlocks, and starvation, and describe mechanisms for thread synchronization (e.g.,…
From PayU Interview Experience | Gurgaon | Senior Software Engineer
- 16
Java StringBuilder vs. String
Explain the differences between Java's String , StringBuilder , and StringBuffer classes. When should one choose StringBuilder over String for concatenation, and what are the performance implications? Discuss their immutability and thread-safety…
From PayU Interview Experience | Gurgaon | Senior Software Engineer
Payu interview questions FAQ
What questions are asked in Payu interviews?
Candidates reported 40 distinct questions across 7 Payu interviews. 17 coding and DSA questions, 7 system design questions, 16 other questions.
Which Payu interview questions are asked most often?
The most repeated are "Two Sum Problem" (2 times).
How difficult are Payu interview questions?
Of the questions candidates rated, 40% were easy, 50% medium and 10% hard.