Solve maze reachability and two follow-ups

You are given three independent coding tasks. ## 1) Maze reachability with “rolling ball” movement Given an `m x n` grid `maze` where `0` means empty and `1` means wall, a ball starts at `start = (sr, sc)` and wants to reach `destination = (dr, dc)`. Movement rule: from any cell, you may choose one of 4 directions (up/down/left/right). The ball then **rolls** in that direction until the next step would hit a wall or go out of bounds; it **stops at the last valid empty cell** before the obstacle. You may then choose a new direction. Return whether the ball can stop **exactly** at `destination`. **Input:** `maze: int[m][n]`, `start: int[2]`, `destination: int[2]` **Output:** `bool` **Constraints (typical):** `1 ≤ m,n ≤ 100`, `maze[i][j] ∈ {0,1}`, start/destination are empty. ## 2) Compute the diameter of a binary tree Given the root of a binary tree, compute its **diameter**, defined as the maximum number of **edges** on any path between two nodes in the tree. **Input:** `root` (binary tree) **Output:** `int` ## 3) Exclusive time of functions from logs There are `n` single-threaded functions labeled `0..n-1`. You are given a list of logs in chronological order. Each log is a string in the format: - `"id:start:timestamp"` or - `"id:end:timestamp"` Rules: - A function can call other functions; the CPU executes only the top of the call stack. - `end:timestamp` is **inclusive** (i.e., the function runs through that timestamp). Return an array `ans` where `ans[i]` is the **exclusive** time spent in function `i`. **Input:** `n: int`, `logs: string[]` **Output:** `int[]` **Constraints (typical):** `1 ≤ n ≤ 100`, `1 ≤ logs.length ≤ 10^4`, timestamps are non-decreasing integers.