使用模板的 C++ 链表

Question

我想使用模板在 C++ 中实现我自己的链表。但是，我遇到了几个编译器错误。这是代码:

template <class T>
class Node{
T datum;
Node _next = NULL;
 public:
 Node(T datum)
{
    this->datum = datum;
}
 void setNext(Node next)
 {
     _next = next;
 }
 Node getNext()
 {
     return _next;
 }
 T getDatum()
 {
     return datum;
 }          
};
template <class T>
class LinkedList{
Node<T> *node;
Node<T> *currPtr;
Node<T> *next_pointer;
int size;
public:
LinkedList(T datum)
  {
      node = new Node<T>(datum);
      currPtr = node;  //assignment between two pointers.
      size = 1;
  }
void add(T datum)
 {
   Node<T> *temp = new Node<T>(datum);
   (*currPtr).setNext((*temp));
   currPtr = temp;       
   size++;
 }
T next()
{
   next_pointer = node;
   T data = (*next_pointer).getDatum();
   next_pointer = (*next_pointer).getNext();
   return data;
}
int getSize()
{
   return size;
}   
};

当我尝试实例化这个类时，出现以下错误:

LinkedList.cpp: In instantiation of `Node<int>':
LinkedList.cpp:35:   instantiated from `LinkedList<T>::LinkedList(T) [with T = int]'
LinkedList.cpp:60:   instantiated from here
LinkedList.cpp:7: error: `Node<T>::_next' has incomplete type
LinkedList.cpp:5: error: declaration of `class Node<int>'
make[2]: *** [build/Debug/Cygwin-Windows/LinkedList.o] Error 1
make[1]: *** [.build-conf] Error 2
make: *** [.build-impl] Error 2

我正在使用 NetBeans IDE。有人可以给我一些改进建议吗？非常感谢!!

Answer 1

就像你做 Node<T> *node; 时一样在LinkedList , 你也需要在你的 Node 中做同样的事情类

template <class T>
class Node{
    T datum;
    Node<T> *_next;//template parameter
                   //also, need to make this a pointer and initialized in constructor
public:

//...
    void setNext(Node<T> next) //template parameter
    {
        _next = next;
    }
    Node<T> getNext() //template parameter
    {
        return _next;
    }
//...
};