leetcode

0 class Solution {

1 public:

2 vector<int> inorderTraversal(TreeNode *root) {

3 vector<int> res;

4 stack<TreeNode *> st;

5

6 while (true) {

7 while (root) {

8 st.push(root);

9 root = root->left;

10 }

11

12 if (!st.empty()) {

13 root = st.top();

14 st.pop();

15 res.push_back(root->val);

16 root = root->right;

17 } else

18 return res;

19 }

20

21 return res;

22 }

23 };