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#include <iostream>
#include <string>

using namespace std;

template <class T>
class Node{
        friend class LinkedList<T>;
private:
    T data;
    Node <T> *next;
public:
    Node();
    Node(T d);
    ~Node();
};

template <class T>
Node<T>::Node(){
    T data = 0;
    next = 0;
}

template <class T>
Node<T>::Node(T d){
    data = d;
    next = 0;

}

template<class T>
Node<T>::~Node(){
    delete next;
}

template <class T>
class LinkedList{
private: 
    Node <T> *head;
public:
    LinkedList();
    ~LinkedList();
    void Push_Front(const T& e);
}

template<class T>
LinkedList <T>::LinkedList(){
    head = 0;
}

template <class T>
LinkedList<T>::~LinkedList(){
    delete head;
}

template <class T>
void LinkedList<T>::Push_Front(const T &e){
    Node<T> *newNode = new Node<T>(e);

    if(head == 0)
        head = new Node<T>(e);

    newNode->next = head;
   head = newNode;
}


void main(){
    LinkedList<int> list;

    list.Push_Front(10);


    int t;
    cin>>t;
    return ;
}

我正在尝试编写链表的模板版本。我遇到了一些错误，不知道为什么。当我尝试结交朋友类 LinkedList 时发生错误，我需要这样做，以便我可以从 LinkedList 访问 T 数据。

: error C2059: syntax error : '<'
: see reference to class template instantiation 'Node<T>' being compiled
: error C2238: unexpected token(s) preceding ';'
: error C2143: syntax error : missing ';' before 'template'
: error C2989: 'LinkedList' : class template has already been declared as a non-class template
: see declaration of 'LinkedList'
: 'LinkedList': multiple template parameter lists are not allowed
: error C2988: unrecognizable template declaration/definition
: error C2059: syntax error : '<'
: error C2588: '::~LinkedList' : illegal global destructor
: fatal error C1903: unable to recover from previous error(s); stopping compilatio
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1 回答 1

3

您在 . 的类定义末尾缺少一个分号LinkedList。但是，即使您解决了这个问题，由于Node<T>需要了解LinkedList<T>，反之亦然，您需要在顶部声明它们：

#include <iostream>
#include <string>

using namespace std;

template <typename T> class Node;
template <typename T> class LinkedList;

//Code as before
于 2012-11-27T04:49:15.283 回答