Cracking the (Frontend) Coding Interview

Overview

This article explores a strategy for tackling frontend engineering interviews by adapting data structures and algorithms questions to the DOM. The author shares their experience interviewing for frontend roles and highlights the importance of understanding core JavaScript concepts and DOM manipulation. The focus is on using Vanilla JS to solve problems, emphasizing practical skills applicable in interview settings.

Interview Rounds

The author outlines an approach that involves transposing traditional DS/A questions into frontend-related problems. The core idea is that the DOM, being a tree-like structure, lends itself well to problems involving graphs, linked lists, and trees. This allows candidates to demonstrate their understanding of both CS fundamentals and frontend technologies.

The example problem presented is:

Question: Return the kth to last element of a singly linked list.

This is then adapted to the following frontend question:

Frontend Question: Change the background color of the kth to last sibling element, given access only to the nextElementSibling method and inline styling.

The article then explores several approaches to solving the problem:

1. Turning the linked list into a doubly linked list.
2. Determining the length of the linked list and then iterating again.
3. Using recursion.
4. Using two pointers simultaneously.

The author demonstrates the two-pointer approach with example HTML and JavaScript code. The provided solution has O(n) time complexity and O(1) space complexity.

Key Takeaways

• DS/A in the DOM: Practice translating data structures and algorithms questions into DOM manipulation problems.
• Vanilla JS Proficiency: Hone skills in Vanilla JS to avoid reliance on frameworks during interviews.
• Problem-Solving Strategies: Brainstorm multiple solutions before coding, and prioritize a working solution over immediate optimization.
• Two-Pointer Technique: Understand and apply the two-pointer technique for linked list problems in the DOM.
• Communicate Clearly: Articulate the thought process and trade-offs involved in different solution approaches.