leetcode-daily/cpp/2205/220524-CN.cpp

28 lines
722 B
C++

#include <functional>
struct TreeNode {
int val;
TreeNode* left;
TreeNode* right;
explicit TreeNode(int x = 0, TreeNode* l = nullptr, TreeNode* r = nullptr) : val(x), left(l), right(r) {}
};
/**
* 965. Univalued Binary Tree
* A binary tree is uni-valued if every node in the tree has the same value.
* Given the root of a binary tree, return true if the given tree is uni-valued, or false otherwise.
*/
class Solution {
public:
static bool isUnivalTree(TreeNode* root) {
if (!root)
return true;
std::function<bool(const TreeNode*)> dfs = [&](const TreeNode* ptr) {
return !ptr || (ptr->val == root->val && dfs(ptr->left) && dfs(ptr->right));
};
return dfs(root->left) && dfs(root->right);
}
};