The Peak Trail

A 'Mountain Path' in a tree of integers is a simple path that strictly increases to a peak node and then strictly decreases. A path must have at least one increasing step and at least one decreasing step (length >= 2, with a clear peak). Find the number of nodes in the longest Mountain Path (the count of nodes, not edges). Input Format: - Line 1: N, the number of nodes. - Line 2: N integers, the value at each node (1-indexed). - Next N-1 lines: u v (edge between u and v). Output Format: - An integer representing the maximum nodes in a Mountain Path. If no such path exists, output 0. Example: Input: 5 1 3 5 3 1 1 2 2 3 3 4 4 5 Output: 5 (Path 1-2-3-4-5 has values 1, 3, 5, 3, 1. It increases then decreases.)