圖片.png

• 思路 以及算法過程：

  
  
  圖片.png

• code:

#include<iostream>
using namespace std;
#include<vector>
#include<algorithm>
#include<unordered_map>
#include<queue>
#include<stack>
#include<string>
#include <set>
#include <unordered_set>
#include <map>
//* Definition for a binary tree node.
struct TreeNode {
    int val;
    TreeNode *left;
    TreeNode *right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};
//Definition for singly-linked list.
struct ListNode {
     int val;
     ListNode *next;
     ListNode(int x) : val(x), next(NULL) {}
 }


//my
class Solution {
public:
    vector<TreeNode *> stk;
    TreeNode* maxTree(vector<int> A) {
        vector<TreeNode*> tempM;
        if (A.empty())
            return {};
        for (auto aa : A) {
            TreeNode* tar = new TreeNode(aa);
            while (tempM.size() > 0&& aa>tempM[tempM.size() -1]->val) {
                tar->left = tempM[tempM.size() - 1];
                tempM.pop_back();
            }
            if (tempM.size() != 0) {
                tempM[tempM.size() - 1]->right = tar;
            }
            tempM.push_back(tar);
        }
        return tempM[0];
    }
};

int main()
{
    vector<int> aa = { 2, 5, 6, 0, 3, 1 };
    Solution ss;
    auto ans =ss.maxTree(aa);
    //vector<vector<int>> ans(23, vector<int>());

    getchar();
    return 0;
}