107.Binary Tree Level Order Traversal II.cpp

class Solution {
public:
    vector<vector<int>> levelOrderBottom(TreeNode* root) {
        vector<vector<int> >res;
        if(root==NULL)  return res;
        queue<TreeNode*>q;
        q.push(root);
        while(!q.empty()){
            int n=q.size();
            vector<int>tem;
            for(int i=0;i<n;i++){
                TreeNode* temp=q.front();
                tem.push_back(temp->val);
                if(temp->left)   q.push(temp->left);
                if(temp->right)   q.push(temp->right);
                q.pop();
            }
            res.push_back(tem);
        }
        reverse(res.begin(),res.end());
        return res;
    }
};
//加油啊，看了爆裂鼓手还是很震惊的