问题描述： Given a binary tree, return all duplicate subtrees. For each kind of duplicate subtrees, you only need to return the root node of any one of them. Two trees are duplicate if they have the

题目： Given a binary tree, count the number of uni-value subtrees. A Uni-value subtree means all nodes of the subtree have the same value. For example: Given binary tree, 5/ \1 5/

题目链接 https://acm.bnu.edu.cn/v3/problem_show.php?pid=52310 problem description Define the depth of a node in a rooted tree by applying the following rules recursively: • The depth of a root node is

参考：点击打开链接 /*** Definition for a binary tree node.* public class TreeNode {* int val;* TreeNode left;* TreeNode right;* TreeNode(int x) { val = x; }* }*/public class Solution {priva

图片来源： https://blog.csdn.net/dylan_frank/article/details/78177368       【题意】： 　　对于每一个节点来说有多少对相同的子树。 【题解】： 　　利用层数进行hash，返回到对应的节点，最后标记后用等差数列来求出所有方案数。   1 #pragma GCC optimize(2) 2 #include<bits/s