APIwiz interview questions

📌 Round 1: Assignment Round (Shortlisting Round) Before the interview, all candidates had to complete a take-home assignment. Assignment: Build a JSON Tree Visualizer We were required to develop a web application that could: Parse and display a JSON input as an expandable/collapsible tree structure Support nested JSON Include UI features specified by the company (expand all/collapse all, styling, etc.) Ensure clean, readable, and modular code structure Demonstrate understanding of React, component design, and state handling This assignment was used to shortlist candidates for the interview. 📌 Round 2: Technical Interview 1. JavaScript & React Theory The interview started with core JS and React concepts: Difference between var, let, and const Reconciliation in React Closures in JavaScript I answered all theory questions correctly. 2. JavaScript Output-Based Snippets The interviewer asked multiple short JS code snippets and asked for the output. I was correct in some (around 70–30 accuracy) For the ones I missed initially, I could explain the logic correctly once the code was run 3. Coding Round I was given 3 coding problems: Q1: Flattening a Deeply Nested Array Example: Input: [1, [2, [3, [4, [5]]]]] Output: [1, 2, 3, 4, 5] I was not able to solve this one during the interview. Q2: Find Missing Numbers in an Array I solved this successfully. Q3: String Compression Input: "aaaabbbcc" Output: "a4b3c2" I solved this one completely. 4. React Debugging Round The last part was the hardest: The interviewer shared a large React codebase (an e-commerce website) I was given 4 user-reported issues I had to read the code and debug the problems I struggled in this section and was not able to debug the full code within time. 📌 Overall Experience The interviewer was friendly and focused heavily on: JavaScript fundamentals Problem-solving Ability to debug real-world React codebases Theory + DSA went well, but the debugging section was the most challenging part.