Leetcode学习笔记:#543. Diameter of Binary Tree
Given a binary tree, you need to compute the length of the diameter of the tree. The diameter of a binary tree is the length of the longest path between any two nodes in a tree. This path may or may not pass through the root.
实现:
int max = 0;
public int diameterOfBinaryTree(TreeNode root) {
maxDepth(root);
return max;
}
private int maxDepth(TreeNode root) {
if (root == null) return 0;
int left = maxDepth(root.left);
int right = maxDepth(root.right);
max = Math.max(max, left + right);
return Math.max(left, right) + 1;
}
思路:
前序遍历二叉树,用max保存当前最大值并决定是否更新