Hi everyone,

I am preparing for an upcoming E4 loop interview for meta in the next week and would like to understand the best practices for representing and explaining a binary tree in CoderPad, especially for problems like 543. Diameter of Binary Tree.

I wonder how do we represent graphs and trees when you want to trace it. I usually do very well with array explanations, I know exactly how to represent pointers that move in an array and all the important variables that are needed. But when it comes to graphs and trees I struggle to picturize or represent the example in coderpad and go about with explanations.

Specifically, I am curious about:

Representation of the Binary Tree:

How do interviewers typically provide a binary tree structure in CoderPad?
Should I assume a specific TreeNode class, or do I define it myself?
Variables for DFS Explanation:

What key variables should I introduce to effectively explain a DFS recursive solution?
How can I walk through a simple binary tree example step-by-step to show how the recursion and updates work?
Tracing Without Execution:

During the interview, how can I trace the solution (e.g., diameter calculation) without executing the code?
How should I visually represent or explain the recursive calls and updates (like res for the maximum diameter)?
An example approach or any tips to communicate this solution effectively during the interview would be greatly appreciated!

Thanks in advance for your help! 😊