用极简约束搭建长期可维护的个人系统

#include <iostream>
#include <random>
#include <chrono>
 
using namespace std;
 
struct TreeNode {
    int val;
    TreeNode *left;
    TreeNode *right;
 
    TreeNode() : val(0), left(nullptr), right(nullptr) {
    }
 
    TreeNode(int x) : val(x), left(nullptr), right(nullptr) {
    }
 
    TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {
    }
};
 
class Solution {
public:
    bool isValidBST(TreeNode* root) {
        if(!root) return true;
        bool l = isValidBST(root->left);
        bool r = isValidBST(root->right);
        if(!l || !r) return false;
        if(root->left && root->left->val >= root->val) return false;
        if(root->right && root->right->val >= root->val) return false;
        return true;
    }
};
 
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    Solution s;
    TreeNode *root = new TreeNode(2);
    root->left = new TreeNode(1);
    root->right = new TreeNode(3);
    s.isValidBST(root);
   //  cout << p << endl;
    return 0;
}