17 questions · from 3 interviews
Chargebee interview questions
Every question candidates reported from their Chargebee interviews, most frequently asked first. Each links to the write-up it came from, so you can see the round and how it went.
Chargebee coding and DSA questions
- 01
Longest Non‑Repeating Character Sequence
Given a string, find the length of the longest substring that contains no repeating characters.
- 02
Flatten an Array
Given a nested array of integers (e.g., [1, [2, 3], [[4]], 5]), flatten it into a single‑level array containing all the integers in order (e.g., [1, 2, 3, 4, 5]).
- 03
Find the 3rd Highest Salary (SQL)
Write an SQL query to retrieve the third highest salary from the Employee table.
- 04
Design a Queue Using Arrays
Design a queue data structure that uses an array for storage, supporting enqueue and dequeue operations with appropriate handling of overflow and underflow.
- 05
Chess Piece X Possible Moves
Given an 8x8 chess board and a piece X, find all its possible moves. Specifically, I was asked to solve for knight moves, expecting an approach other than a naive one.
Easy · From Chargebee | Software Engineer | Backend | June 2024
- 06
Numbers with Prime Set Bit Count
Given a range [A, B], find all numbers within this range whose set bit (1) count is a prime number.
- 07
SQL Query for N Doses Vaccinated
Write a SQL query to find individuals who have received exactly 'n' doses of a vaccine, where n can be any non-negative integer (n=0).
- 08
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. Both recursive and iterative approaches were discussed during the interview.
Easy · From Chargebee | Interview Experience | SDE 1 | Offer
- 09
Second Highest Salary
Write an SQL query to report the second highest salary from an Employee table. If there is no second highest salary, the query should report null. This problem specifically required a solution without using the LIMIT clause.
Easy · From Chargebee | Interview Experience | SDE 1 | Offer
Chargebee system design questions
- 01
Design Auto Increment Feature
I was asked to explain my approach to designing an auto-increment feature that supports multiple sequences concurrently and includes a reset mechanism.
- 02
Vaccination Tracking System Database Choice and Design
I was asked to choose an appropriate database for a vaccination tracking system (I suggested MySQL), and then design a schema for it.
- 03
Payment Gateway Retry Scenarios
I was asked to describe scenarios in which I would implement retries if I were integrating a payment gateway.
- 04
Preventing Unnecessary Payment Retries
Assuming I was part of a payment gateway team, how would I ensure that clients do not make unnecessary retries for payments?
- 05
Stopping Retries for Successful Payments
How would I prevent a client from retrying a payment that has already been successfully processed?
- 06
Design NEET Result Publishing Website
I was tasked with designing a system for a NEET (National Eligibility cum Entrance Test) result publishing website, specifically addressing how to handle quick traffic spikes.
- 07
Design BookMyShow Seat Booking System
Design the High-Level Design (HLD) for a seat booking algorithm similar to BookMyShow, with a primary focus on handling concurrency.
Chargebee other questions
- 01
Find the Fastest 3 Horses Puzzle
A classic puzzle: Given 25 horses and a track that can race 5 horses at a time, what is the minimum number of races needed to find the fastest 3 horses? I was provided with a link to GeeksforGeeks.
Chargebee interview questions FAQ
What questions are asked in Chargebee interviews?
Candidates reported 17 distinct questions across 3 Chargebee interviews. 9 coding and DSA questions, 7 system design questions, 1 other questions.