CSES 1131 Tree Diameter - Problem Statement

Find the diameter of a tree with $n$ nodes and $n-1$ edges. Unlike the binary tree version, nodes can have any number of children. The input is an adjacency list, not pointer-based TreeNode objects.

The DP approach from LC $543$ still works here, but Double BFS gives a cleaner solution for general trees. You will solve this problem fully in the Tree Diameter & Center section using Double BFS. That section also compares both approaches side by side so you can see when each one fits better.