图的邻接表的类实现

const int DefaultVertices = 30;
template<class T,class E>
struct Edge{
    int dest;  //边结点定义
    Edge<T,E> *link;   //下一条边链指针
    Edge(){}
    Edge(int num,E weight):dest(num),link(NULL) {}
    bool operator!=(Edge<T,E>& R)const{
    return (dest!= R.deat)? true :false;
    }
};

template<class T,class E>
struct Vertex{
    T data;   //顶点名字
    Edge<T,E> *adj;   //边链表的头指针
};
template <class T,class E>
class Graphlnk  //注意这里没用继承
{   public:
      Graphlnk(int sz=DefaultVertices);
      ~Graphlnk();
       T getValue(int i) {  return (i>=0 &&i<numVertices)?NodeTable[i].data : 0;  }
       int getVnum() { return numVertices; }
       int getEnum() { return numEdges; }
       bool insertVertex (const T& vertex);
       bool insertEdge (int v1, int v2);
       int getFirstNeighbor (int v);
       int getNextNeighbor (int v, int w);
       void input();
       void output();
        int getVertexPos (T& vertex)    //给出顶点vertex在图中的位置
        {       for (int i=0; i <numVertices; i++)
            if (NodeTable[i].data == vertex) return i;
         return -1;
         }
   private:
        int maxVertices,numVertices,numEdges;    //必须加上这3个数据成员,分别为当前最大顶点数，当前顶点数，当前边数
        Vertex<T, E> *NodeTable;             //顶点表 (各边链表的头结点)
};

 template <class T, class E>
void Graphlnk<T, E>::input()
{  int i,j,k,vn,en;      //vn表示顶点数，en表示边数
   T v1,v2;
   cout<<"输入顶点数和边数：\n";
   cin>>vn>>en;
   for(i=0;i<vn;i++)
   {   cin>>v1;
       insertVertex(v1);   }
   i=0;
   while(i<en)
   {     cout<<"输入边的两个顶点：";
         cin>>v1>>v2;
         j=getVertexPos(v1);
         k=getVertexPos(v2);
        if(j==-1 || k==-1)
            cout<<"重新输入边的两个顶点信息！"<<endl;
       else
              {  insertEdge(j,k);
          i++;
    }
   }
}

template <class T, class E>
void Graphlnk<T, E>::output()
{   int i,vn,en;
    Edge<T,E> *p;
    vn=numVertices;   en=numEdges;
   cout<<endl<<"图的顶点数="<<vn<<"边数="<<en<<endl<<endl;
    for(i=0;i<vn;i++)
   {   cout<<i<<": "<<NodeTable[i].data;
       p=NodeTable[i].adj;
      while(p!=NULL)
         {   cout<<"-->"<<p->dest;    p=p->link;        }
       cout<<endl;
   }
}

template<class T,class E>
Graphlnk<T,E>::Graphlnk(int sz){
    maxVertices = sz;
    numVertices = 0;
    numEdges = 0;
    NodeTable = new Vertex<T,E>[maxVertices];  //创建顶点表数组
    if(NodeTable == NULL){
        cout << "存储分配错误!" << endl;exit(1);
    }
    for(int i = 0;i < maxVertices;i++)NodeTable[i].adj = NULL;
}

template<class T,class E>
Graphlnk<T,E>::~Graphlnk(){
    for(int i =0;i<numVertices;i++){
        Edge<T,E> *p = NodeTable[i].adj;
        while(p != NULL){
            NodeTable[i].adj = p->link;
            delete p ;
            p = NodeTable[i].adj;
        }
    }
    delete[] NodeTable;  // 删除顶点表数组
}

template<class T,class E>
int Graphlnk<T,E>::getFirstNeighbor(int v){
    if(v != -1){
        Edge<T,E> *p = NodeTable[v].adj;
        if(p!=NULL)return p->dest;
    }
    return -1;
} 

template<class T,class E>
int Graphlnk<T,E>::getNextNeighbor(int v,int w){
    if(v!=-1){
        Edge<T,E> *p=NodeTable[v].adj;
        while(p!=NULL&&p->dest!=w)
        p = p->link;
        if(p!=NULL&&p->link!=NULL)
        return p->link->dest;
    }
    return -1;
}

template<class T,class E>
bool Graphlnk<T,E>::insertVertex(const T& Vertex){
    if(numVertices == maxVertices)return false;
    NodeTable[numVertices].data = Vertex;
    numVertices++;
    return true;
}

template<class T,class E>
bool Graphlnk<T,E>::insertEdge(int v1,int v2){
    if(v1 >=0 && v1 < numVertices && v2>=0 && v2 < numVertices){
        Edge<T,E> *q, *p = NodeTable[v1].adj;
        while(p!=NULL&& p->dest!=2)
        p = p->link;
        if(p!=NULL) return false;
        p = new Edge<T,E>; q = new Edge<T,E>;
        p->dest = v2;
        p->link = NodeTable[v1].adj;
        NodeTable[v1].adj = p;
        q->dest = v1;
        q->link = NodeTable[v2].adj;
        NodeTable[v2].adj = q;
        numEdges++;
        return true;
    }
} 

template <class T, class E>
/*void BFS(Graphlnk<T,E>& G,T& v)
{
    int  i,w,n=G.getVnum();    //此处需修改，类中没定义该函数
    bool *visited=new bool[n];
    LinkedQueue<int> Q;
    printf("\n广度优先搜索顺序为:\n");
    for(i=0; i<n; i++)
    visited[i]=false;
    int loc = G.getVertexPos(v);
    cout << G.getValue(loc) << " " ;
    visited[loc] = true;
    Q.EnQueue(loc);
    while(!Q.IsEmpty()){
        Q.DeQueue(loc);
        w = G.getFirstNeighbor(loc);
        while(w != -1){
            if(visited[w]==false){
                cout << G.getValue(w)<< " ";
                visited[w] = true;
                Q.EnQueue(w);
            }
            w = G.getNextNeighbor(loc,w);
        }
    }
}*/