leetcode116

 class Solution {
 public:
     Node* connect(Node* root) {
         if (root != NULL)
         {
             queue<Node*> Q;
             root->next = NULL;
             Q.push(root);
             while (!Q.empty())
             {
                 vector<Node*> V;
                 while (!Q.empty())
                 {
                     Node* t = Q.front();
                     Q.pop();
                     if (t->left != NULL)
                     {
                         V.push_back(t->left);
                     }
                     if (t->right != NULL)
                     {
                         V.push_back(t->right);
                     }
                 }
                 V.push_back(NULL);
                 for (int i = V.size() - ; i > ; i--)
                 {
                     V[i - ]->next = V[i];
                 }
                 for (int i = ; i < V.size() - ; i++)
                 {
                     if (V[i] != NULL)
                     {
                         Q.push(V[i]);
                     }
                 }
             }
         }
         return root;
     }
 };