leetcode

0 class Solution {

1 public:

2 int minimumOperations(TreeNode *root) {

3 queue<TreeNode *> q;

4 q.push(root);

5 int res = 0;

6 while (!q.empty()) {

7 vector<int> lvl, idx(q.size());

8 for (int k = q.size(); k > 0; k--) {

9 TreeNode *root = q.front();

10 q.pop();

11 lvl.push_back(root->val);

12 if (root->left) q.push(root->left);

13 if (root->right) q.push(root->right);

14 }

15 iota(begin(idx), end(idx), 0);

16 sort(begin(idx), end(idx), [&](const int i, const int j) { return lvl[i] < lvl[j]; });

17 for (int i = 0; i < idx.size(); i++) {

18 for (; idx[i] != i; res++)

19 swap(idx[i], idx[idx[i]]);

20 }

21 }

22 return res;

23 }

24 };