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class Solution {
public:
    vector<vector<int> > levelOrderBottom(TreeNode *root) {
        // IMPORTANT: Please reset any member data you declared, as
        // the same Solution instance will be reused for each test case.
        vector<vector<int>> result;
        result.clear();
        TreeNode **seq = new TreeNode *[1000];
        TreeNode **rseq = new TreeNode *[1000];
        int index = 0;
        seq[index++] = root;
        while(true)
        {
            int top = index;
            index = 0;
            vector<int> tmp;
            tmp.clear();
            for(int i = 0 ;i< top;i++)
            {
                if(seq[i] != NULL)
                {
                    tmp.push_back(seq[i]->val);
                    if (seq[i]->left != NULL)
                    {
                        rseq[index++] = seq[i]->left;
                    }
                    if (seq[i]->right != NULL)
                    {
                        rseq[index++] = seq[i]->right;
                    }
                }
            }
            if(tmp.size() > 0)
                result.push_back(tmp);
            if(index == 0)
                break;
            for(int i = 0;i < index;i++)
            {
                seq[i] = rseq[i];
            }
        }
        vector<vector<int>> ans;
        ans.clear();
        for(int i = result.size() - 1;i >= 0;i--)
        {
            ans.push_back(result[i]);
        }
        return ans;
    }
};