leetcode/lcci/17.12.BiNode/Solution.cpp

29 lines
619 B
C++

/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
TreeNode* prev;
TreeNode* convertBiNode(TreeNode* root) {
TreeNode* dummy = new TreeNode(0, nullptr, root);
prev = dummy;
dfs(root);
return dummy->right;
}
void dfs(TreeNode* root) {
if (!root) return;
dfs(root->left);
prev->right = root;
root->left = nullptr;
prev = root;
dfs(root->right);
}
};