Solution: Longest Path With Different Adjacent Characters

Statement

You are given a rooted tree with $n$ nodes, numbered from $0$ to $n - 1$, where the tree is connected, undirected, and has no cycles. The tree is represented by a 0-indexed array parent of size $n$, where parent[i] is the parent of node $i$. The root node is node $0$, so parent[0] $= -1$.

Additionally, you are provided a string s of length $n$, where s[i] represents the character assigned to node ...