Leetcode 2689. Extract Kth Character From The Rope Tree

Given a rope implemented as a binary tree where leaves hold characters/strings and internal nodes store the length (weight) of their left subtree, return the k-th character of the full concatenated string by traversing the tree using those weights to decide left vs right. Aim for O(height) time by comparing k to left-subtree weights and adjusting k as you descend.