Leetcode:binary Tree level Order traversal II

Given a binary tree, return the bottom-up level order traversal of its nodes ' values. (ie, from the left-to-right, the level by level from the leaf to root).

For example:
Given binary Tree {3,9,20,#,#,15,7} ,

    3   /   9    /   7

Return its bottom-up level order traversal as:

[  [15,7],  [9,20],  [3]]
The subject is very interesting. is to get you from the tail to the top, from left to right, and then output a container that is a <int> container.

1 /**2 * Definition for binary tree3 * struct TreeNode {4 * int val;5 * TreeNode *left;6 * TreeNode *right;7 * TreeNode (int x): Val (x), left (null), right (null) {}8  * };9  */Ten classSolution { One  Public: Avector<vector<int> > out;//Create a new container to return -     voidLeveltraval (vector<treenode* >&Level ) -     { the         if(Level.size () >0) -         { -Vector<treenode*>Nextlevel; -              for(inti =0; I < level.size (); i++) +             { -                 if(level[i]->Left ) +Nextlevel.push_back (level[i]->Left ); A                 if(level[i]->Right ) atNextlevel.push_back (level[i]->Right ); -             } - Leveltraval (nextlevel); -vector<int>Val; -              for(inti =0; I < level.size (); i++) -Val.push_back (level[i]->val); in              out. Push_back (val); -         } to     } +vector<vector<int> > Levelorderbottom (TreeNode *root) { -         //Start Typing your/C + + solution below the         //Do not write int main () function *          out. Clear (); $Vector<treenode*>v;Panax Notoginseng         if(Root! =NULL) -         { the V.push_back (root); + Leveltraval (v); A         } the         return  out; +     } -};

Leetcode:binary Tree level Order traversal II