#include <iostream>
#include <vector>
using namespace std;//双链表节点结构
typedef struct treeNode {int value;struct treeNode* left;struct treeNode* right;treeNode(int x) : value(x), left(nullptr), right(nullptr) {}
} TreeNode;void inOrderTraversal(TreeNode* root) {if (root == nullptr) {return;}inOrderTraversal(root->left);std::cout << root->value << " ";inOrderTraversal(root->right);
}bool isValidBST(TreeNode* root, long long min_val, long long max_val)
{if (root == nullptr){return true;}if (root->value <= min_val || root->value >= max_val){return false;}bool leftBST = isValidBST(root->left, min_val, root->value);bool rightBST = isValidBST(root->right, root->value, max_val);return leftBST & rightBST;
}int main()
{// 示例二叉搜索树TreeNode *root = new TreeNode(2);root->left = new TreeNode(1);root->right = new TreeNode(3);//示例非二叉搜索树//TreeNode *root = new TreeNode(10);//root->left = new TreeNode(20);//root->right = new TreeNode(5);//root->left->left = new TreeNode(4);//root->left->right = new TreeNode(3);std::cout << "Is valid BST: " << isValidBST(root, LONG_MIN, LONG_MAX) << std::endl;system("pause");return 0;
}

https://blog.csdn.net/m0_58086930/article/details/120340917