/**
* 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:
int preroot = 0;
TreeNode* bstToGst(TreeNode* root) {
if(root->right)
bstToGst(root->right);
preroot = root->val = root->val + preroot;
if(root->left)
bstToGst(root->left);
return root;
}
};
![](https://img.laitimes.com/img/9ZDMuAjOiMmIsIjOiQnIsIyZuBnLzYTN3gTO0IjMx0iN1EDN0ETN2EjNwYDM5EDMy0iM2gzNwATMvwlNwkTMwIzLcJjN4cDMwEzLcd2bsJ2Lc12bj5ycn9Gbi52YugTMwIzZtl2Lc9CX6MHc0RHaiojIsJye.png)
转载于:https://www.cnblogs.com/feliz/p/10985894.html