C++ | Leetcode C++题解之 第508题出现次数最多的子树元素和

题目：

题解：

class Solution {unordered_map<int, int> cnt;int maxCnt = 0;int dfs(TreeNode *node) {if (node == nullptr) {return 0;}int sum = node->val + dfs(node->left) + dfs(node->right);maxCnt = max(maxCnt, ++cnt[sum]);return sum;}public:vector<int> findFrequentTreeSum(TreeNode *root) {dfs(root);vector<int> ans;for (auto &[s, c]: cnt) {if (c == maxCnt) {ans.emplace_back(s);}}return ans;}
};