LeetCode/src/main/java/com/cool/hot100/binary_tree/Num543.java

package com.cool.hot100.binary_tree;

/**
 * Created with IntelliJ IDEA.
 *
 * @Author: Cool
 * @Date: 2024/08/28/23:52
 * DayNumber 5
 * Hard 1
 * Level 3
 */
public class Num543 {

    public int diameterOfBinaryTree(TreeNode root) {
        if (root == null) return 0;
        int left = getTreeDeep(root.left);
        int right = getTreeDeep(root.right);
        return left + right;
    }

    private int getTreeDeep(TreeNode root) {
        if (root == null) return 0;
        int res = getTreeDeep(root.left);
        res = Math.max(res, getTreeDeep(root.right));
        return res + 1;
    }

}