图的邻接表存储

#include<iostream.h>
typedef struct node
{
	int adjvex;
	node *next;
	char data;
	bool tag1;
}*ptrn;
class linklist
{
protected:
	int curposition;
	ptrn curptr;
	int count;
public:
    ptrn head;
	void sethead(ptrn &head1)
	{
		head=head1;
		curposition=0;
		curptr=head;
		count=0;
	}
	ptrn getelemptr(int position)
	{
        if(curposition>position)
		{
			curposition=0;
			curptr=head;
		}
		for(;curposition<position;curposition++)
			curptr=curptr->next;
		return curptr;
	}
	int getcurposition()
	{
		return curposition;
	}
	int length()
	{
		ptrn temp;
		temp=head;
		while(1)
		{
			if(temp!=0)
			{
				count++;
				temp=temp->next;
			}
			else
				break;
		}
		return count;
	}
	
	int getelem(int position,int n)//获取链中第position位置的元素，其下标为n
	{
		if(position<1||position>length()+1)
			cout<<"越界"<<endl;
		else
		{
			ptrn tem;
			tem=getelemptr(position);
			n=tem->adjvex;
			return n;
		}
	}
};
typedef struct adjlistgraphvexnode
{
	char ch;
	linklist *adjlink;
}*pt;
class graph
{
private:
	
	int vexnum;
	bool tag;
	char *data1;
	ptrn *vextable;
public:
    pt *vexarray;
	graph(int size)
	{
		
		vexnum=size;
		tag=false;
        data1=new char[vexnum];
		vextable=new ptrn[vexnum];
		vexarray=new pt[vexnum];
	}
	void inputelem()
	{
		cout<<"请输入所有顶点的数据"<<endl;
		for(int i=0;i<vexnum;i++)
		{
			cin>>data1[i];
		}
	}
	void inputgraph()
	{
		ptrn temp,newnode;
		int n,m;
		for(int i=0;i<vexnum;i++)
		{
			vextable[i]=new node;
			temp=vextable[i];
			temp->data=data1[i];
			temp->adjvex=i;
			temp->tag1=tag;
			while(1)
			{
              cout<<"若第"<<i<<"个顶点有邻接点请按1，否则按0"<<endl;
              cin>>n;
			  if(n==1)
			  {
                  newnode=new node;
				  cout<<"请输入顶点"<<i<<"邻接点的数据的下标"<<endl;
				  cin>>m;
				  newnode->data=data1[m];
				  newnode->adjvex=m;
				  newnode->tag1=tag;
				  temp->next=newnode;
				  temp=temp->next;
			  }
			  else
			  {
				  temp->next=0;break;
			  }
			}
		}
	}
	void outputgraph()
	{
		ptrn temp;
		for(int i=0;i<vexnum;i++)
		{
			temp=vextable[i];
			while(1)
			{
				cout<<temp->adjvex<<temp->data<<"  ";
                temp=temp->next;
				if(temp==0)break;
			}
			cout<<endl;
		}
	}
    int indexhelp(linklist *la,int v)//定位顶点v在链表中的位置
	{
		int curpos,adjv;
		curpos=la->getcurposition();
		adjv=la->getelem(curpos,adjv);
		if(adjv==v)return curpos;
		else
		{
            curpos=1;
		    for(curpos=1;curpos<=la->length();curpos++)
			{
			    adjv=la->getelem(curpos,adjv);
			    if(adjv==v)break;
			}
			return curpos;		
		}
		
	}
	int firstadjvex(int v)//返回顶点V的第一个邻接点
	{
		if(v<0||v>=vexnum)
		{cout<<"越界"<<endl;}
		else
		{
			 pt newnode=new adjlistgraphvexnode;                                 
		    vexarray[v]=newnode; 
	    	vexarray[v]->adjlink=new linklist;  
		    ptrn e=vextable[v];
			vexarray[v]->ch=e->data;
		    vexarray[v]->adjlink->sethead(e);                         
		    if(vexarray[v]->adjlink->head==0)                                   
			{return -1;}
		    else
			{
			   int adjv;
                adjv=vexarray[v]->adjlink->getelem(1,adjv);
			   return adjv;
			   
			}
		}
		
	}
	int nextadjvex(int v1,int v2)//返回顶点V1的相对于V2的下一个邻接点
	{
		if(v1<0||v1>=vexnum)cout<<"v1不合法"<<endl;
		if(v2<0||v2>=vexnum)cout<<"v2不合法"<<endl;
		if(v1==v2)cout<<"两者不能相等"<<endl;
		else
		{
			pt newnode=new adjlistgraphvexnode;                                 
	       	vexarray[v1]=newnode; vexarray[v1]->adjlink=new linklist; 
		    ptrn e=vextable[v1];
		    vexarray[v1]->adjlink->sethead(e);
		    if(vexarray[v1]->adjlink->head==0)
			{
				cout<<"没有以"<<v1<<"顶点为头结点的链表"<<endl;
				return -1;
			}
			else
			{
				 int cur=indexhelp(vexarray[v1]->adjlink,v2);
				 if(cur<vexarray[v1]->adjlink->length())
				 {
                      
			              int adjv;
		         	      adjv=vexarray[v1]->adjlink->getelem(cur+1,adjv);
			              return adjv;
				 }
				 else
				 {
                      cout<<v1<<"的邻接点没有"<<v2<<endl;
					  return -1;
				 }
		        
			}
		    
		}
	}
        
};

void main()
{
	graph g(5);
	g.inputelem();
	g.inputgraph();
	g.outputgraph();
	cout<<"第2个顶点的第一个邻接点为"<<g.firstadjvex(2)<<endl;
	cout<<"第2个顶点相对于第一个邻接点的下一个邻接点为"<<g.nextadjvex(2,1)<<endl;
}