指针向量在 push_back 上抛出错误

Question

Spiral/Zigzag level order traversal of binary tree. Initailize vector of pointers to traverse and pop from the front but don't know why its not working

Here is my code sample Code:

void spiralPrint(Node *root)
        {
            if(root!=NULL)
            {
                vector<Node *> v;
                v.push_back(root);
                int j=1;
                while(v.empty() == false)
                {
                    int count = v.size();
                    for(int i=0; i<count; i++)
                    {
                        if(*v.begin()->left != NULL)
                        {
                            v.push_back(*v.begin()->left);
                        }
                        if(*v.begin()->right != NULL)
                        {
                            v.push_back(*v.begin()->right);
                        }
                        v.erase(v.begin());
                    }
                    j++;
                }
            }
        }

Error:

D:\c++\trees\binaryTree.cpp: In function 'void spiralPrint(Node)': 
D:\c++\trees\binaryTree.cpp:136:32: error: request for member 'left' in ' v.std::vector<_Tp,
    _Alloc>::begin<Node, std::allocator<Node> >().gnu_cxx::normal_iterator<_Iterator, _Container>::operator-><Node, std::vector<Node> >()', which is of pointer type 'Node' (maybe you meant to use '->' ?) 
        if(v.begin()->left != NULL) 
        ^~~~ 
        D:\c++\trees\binaryTree.cpp:138:45: error: request for member 'left' in ' v.std::vector<_Tp, _Alloc>::begin<Node, std::allocator<Node> >().gnu_cxx::normal_iterator<_Iterator, _Container>::operator-><Node, std::vector<Node> >()', which is of pointer type 'Node' (maybe you meant to use '->' ?)
        v.push_back(v.begin()->left); 
        ^~~~ 
        D:\c++\trees\binaryTree.cpp:140:32: error: request for member 'right' in ' v.std::vector<_Tp, _Alloc>::begin<Node, std::allocator<Node> >().gnu_cxx::normal_iterator<_Iterator, _Container>::operator-><Node, std::vector<Node> >()', which is of pointer type 'Node' (maybe you meant to use '->' ?) 
        if(v.begin()->right != NULL) 
        ^~~~~ 
        D:\c++\trees\binaryTree.cpp:142:45: error: request for member 'right' in ' v.std::vector<_Tp, _Alloc>::begin<Node, std::allocator<Node> >().gnu_cxx::normal_iterator<_Iterator, _Container>::operator-><Node, std::vector<Node> >()', which is of pointer type 'Node' (maybe you meant to use '->' ?)
        v.push_back(*v.begin()->right); 

Answer 1

Here's the fix

for(int i=0; i<count; i++)
   {
      auto it = *v.begin();
      if(it->left != NULL)
      {
          v.push_back(it->left);
      }
      if(it->right != NULL)
      {
          v.push_back(it->right);
      }
      v.erase(v.begin());
   }

Also with front

for(int i=0; i<count; i++)
   {
       if(v.front()->left != NULL)
       {
          v.push_back(v.front()->left);
       }
       if(v.front()->right != NULL)
       {
          v.push_back(v.front()->right);
       }
       v.erase(v.begin());
   }