leetcode

0 class Solution {

1 public:

2 TreeNode *constructFromPrePost(const vector<int> &pre, const vector<int> &post) {

3 vector<TreeNode *> s = {new TreeNode(pre[0])};

4 for (int i = 1, j = 0; i < pre.size(); i++) {

5 TreeNode *node = new TreeNode(pre[i]);

6 while (s.back()->val == post[j])

7 s.pop_back(), j++;

8 (!s.back()->left ? s.back()->left : s.back()->right) = node;

9 s.push_back(node);

10 }

11 return s.front();

12 }

13 };