这个是个通讯录的源代码，在删除联系人那里出了问题，求解决方法
#include <iostream.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <iomanip.h>
#include <fstream.h>
//--------------------------------------------------------------节点类的定义ok
class node
{
     char name[15];
     int op,hp;
     char mp[15];
     char em[20];
     node *next;
public:
     node(char *n="a",int o=0,int h=0,char *m="b",char *e="c",node *ne=NULL)//初始化
     {
         if(n)strcpy(name,n);
         if(m)strcpy(mp,m);
         if(e)strcpy(em,e);
         next=ne;
         op=o;hp=h;
      }
     void show()//显示节点数据
     {
         cout<<setw(10)<<name<<setw(11)<<op<<"(0)"<<setw(11)<<hp<<"(H)"<<setw(14)<<mp<<"(M)"<<' '<<em<<endl;
     }
     void setname(char *s)//重置姓名
     {strcpy(name,s);}
     void setop(int x)//重置office电话
     {op=x;}
     void sethp(int x)//重置home电话
     {hp=x;}
     void setmp(char *s)//重置mobile电话
     {strcpy(mp,s);}
     void setem(char *s)//重置email
     {strcpy(em,s);}
    
     friend class addr;
     friend istream& operator>>(istream &,node *);//>>的重载
};
//--------------------------------------------------------------节点定义结束
//--------------------------------------------------------------链表创建ok
class addr
{
     node *head;
     node *tail;
     int t;
public:
     addr(node *h=NULL,node *ta=NULL,int tag=1)
     {head=h;tail=ta;t=tag;}
    
     void addtail(node *p)//--------------------------------------------------------------添加到尾部ok
     {
         tail->next=p;
         tail=p;
     }
     void addsort(node *p)//--------------------------------------------------------------按序添加ok
     {


         node *p1,*p2;
         p1=head;p2=head;
        
         if(t==1)//姓名插入
         {
             if (head==NULL){head=p;tail=head;}
             else if (strcmp(p->name,head->name)==-1){p->next=head;head=p;}
             else if(strcmp(p->name,tail->name)>=0) {tail->next=p;tail=p;}
             else
             {   
                 while (strcmp(p2->name,p->name)==-1)//p2.name<p.name
                 {
                     p1=p2;
                     p2=p2->next;
                 }
                 p->next=p2;
                 p1->next=p;
             }
         }
         if (t==2)//office电话插入
         {
             if (head==NULL){head=p;tail=head;}
             else if (p->op<=head->op){p->next=head;head=p;}
             else if(p->op>=tail->op) {tail->next=p;tail=p;}
             else
             {
                 while (p->op>=p2->op)//p2.op<p.op
                 {
                     p1=p2;
                     p2=p2->next;


                 }
                 p->next=p2;
                 p1->next=p;
             }
         }
     }
     void sort()//--------------------------------------------------------------排序ok
     {
         addr s2;
         s2.sett(t);
         node *p=head;
         while(p)
         {
             node *p1=new node;
             node *p2;
             strcpy(p1->name,p->name);
             strcpy(p1->mp,p->mp);
             strcpy(p1->em,p->em);
             p1->op=p->op;
             p1->hp=p->hp;
             s2.addsort(p1);
             p2=p;
             p=p->next;
             delete p2;
         }
         s2.showall();
         head=s2.head;
         s2.head=NULL;
         tail=s2.tail;
         s2.tail=NULL;
     }
    
     node *lookup(char *na)//--------------------------------------------------------------查找ok
     {
         node *p1;
         p1=head;
         while (p1)
         {   
             if (strcmp(p1->name,na)==0) break;
             else p1=p1->next;
         }


         return(p1);
     }
    void deletea(char *na)//--------------------------------------------------------------删除ok
    {
        node *p,*p1;
        p=lookup(na);
        char s;
        cin>>s;
        if (p->name&&p!=head)
            {
                p1=head;
                while(p1->next!=p)p1=p1->next;
                p1->next=p->next;
            }
            if(p==head) {head=p->next;}
            if (p->next==NULL) {tail=p1;p1->next=NULL;}
            if (p->name) delete p;
    }
    void showall()//--------------------------------------------------------------显示全部节点+每屏显示十个ok
    {
        node *p1=head;int k=0;
        system("cls");
        if(p1==NULL) cout<<"No information"<<endl;
        while (p1)
        {   
            k++;
            p1->show();
            p1=p1->next;
            if(k%10==0){system("pause");system("cls");}
        }    
    }
    void sett(int tag){t=tag;}//--------------------------------------------------------------重置tag ok
    int gett(){return(t);}//--------------------------------------------------------------取tag ok
    node *gethead(){return head;}//--------------------------------------------------------------取head ok
    void creatlist(char *filename)//--------------------------------------------------------------文件读>>重载ok
    {
        ifstream in(filename);
        if(!in){cout<<"wrong name"<<endl;}
        else


        {    int n;
            in>>n;
            for(int i=1;i<=n;i++)
            {
                node *s=new node;
                in>>s;
                addsort(s);
            }
        }
        in.close();
    }
   
    void writelist(char *filename)//--------------------------------------------------------------文件写ok
      {
         
          ofstream out(filename);
         if (head)
         {
              node *p1=head;
             while (p1!=tail)
             {    
                 out<<setw(10)<<p1->name<<setw(11)<<p1->op<<"(0)"<<setw(11)<<p1->hp<<"(H)"<<setw(14)<<p1->mp<<"(M)"<<' '<<p1->em<<endl;
                 p1=p1->next;
             }
             out<<setw(10)<<tail->name<<setw(11)<<tail->op<<"(0)"<<setw(11)<<tail->hp<<"(H)"<<setw(14)<<tail->mp<<"(M)"<<' '<<tail->em<<endl;
             out.close();
         }
      }
     void writelistbin()//--------------------------------------------------------------文件二进制写ok
      {
         
         ofstream out("data.bin",ios::out|ios::binary);
         if (head)
         {
              node *p1=head;


             while (p1)
             {    
                 int l;
                 l=strlen(p1->name);
                 out.write((char *)&p1->name,l);out<<' ';
                 out.write((char *)&p1->op,4);out<<' ';
                 out.write((char *)&p1->hp,4);out<<' ';
                 l=strlen(p1->mp);
                 out.write((char *)&p1->mp,l);out<<' ';
                 l=strlen(p1->em);
                 out.write((char *)&p1->em,l);out<<endl;
                 p1=p1->next;
             }
             out.close();
         }
      }
    ~addr()
    {
        node *p1=head;
        while(head)
        {
           p1=head;
           head=head->next;
           delete p1;;
        }
    }
};
//---------------------------------------------------------------------创建链表结束
istream& operator>>(istream &in,node *s)//------------------------------------->>的重载
{
     in>>s->name>>s->op>>s->hp>>s->mp>>s->em;
     return in;
}
addr s1;
void add(void)//--------------------------------------------------------------菜单定义1 添加
{
   node *s=new node;
   cin>>s;
   s1.addsort(s);
}
void del()//-------------------------------------------------------------------菜单定义2 删除
{
     char name[15];
     cin>>name;


     s1.deletea(name);
}
void find()//------------------------------------------------------------------菜单定义4 查找
{
     char name[15];int c;
     node *p;
     cout<<"1.By name"<<endl;
     cout<<"2.By fristname"<<endl;
     cin>>c;
     cout<<"Input the key word:"<<endl;
     cin>>name;
     if(c==1)
     {
         p=s1.lookup(name);
         if(p)p->show();
         else cout<<"Sorry,can' find !"<<endl;
     }
     if(c==2)s1.lookup(name);
}
void modify()//--------------------------------------------------------------------菜单定义5 修改
{
     char name[15];node *p;
     char *ss[5]={"1.Change name",
                  "2.change office phone",
                  "3.Change home phone",
                  "4.Change mobile phone",
                  "5.Change email"};
     cin>>name;
     p=s1.lookup(name);
     if(p)
     {
     p->show();
     cout<<"Pick your choice:"<<endl;
     for (int j=0;j<5;j++)cout<<ss[j]<<endl;
     int i;
     cout<<"Choice:";
     cin>>i;
     switch (i)
     {
     case 1:
         char sn[15];
         cout<<"input the new name:";
         cin>>sn;
         p->setname(sn);
         p->show();
         if (s1.gett()==1)s1.sort();
         break;
     case 2:
         int so;
         cout<<"input the new number:";
         cin>>so;
         p->setop(so);


         p->show();
         if (s1.gett()==2)s1.sort();
         break;
     case 3:
         int sh;
         cout<<"input the new number:";
         cin>>sh;
         p->sethp(sh);
         p->show();
         break;
     case 4:
         char sm[15];
         cout<<"input the new number:";
         cin>>sm;
         p->setmp(sm);
         p->show();
         break;
     case 5:
         char se[20];
         cout<<"input the new email:";
         cin>>se;
         p->setem(se);
         p->show();
         break;
     }
     }else cout<<"srooy,can't find!"<<endl;
}
void addtxt()//--------------------------------------------------------------菜单定义6 批量添加
{
     char name[15];
     cin>>name;
     s1.creatlist(name);
}
void writetxt()//--------------------------------------------------------------菜单定义7 批量写出
{
     char name[15];
     cin>>name;
     s1.writelist(name);
}
void addsort()//--------------------------------------------------------------菜单定义8 排序
{
     int k=s1.gett();
     char ss;
     if(k==1)
     {
         cout<<"Sort by name,do you want to change? [Y//N]"<<endl;
         cin>>ss;
          if (ss=='Y'||ss=='y') {s1.sett(2);s1.sort();}
     }
     if(k==2)
     {
         cout<<"Sort by officenumber,do you want to change? [Y//N]"<<endl;
         cin>>ss;
          if (ss=='Y') {s1.sett(1);s1.sort();}


     }
    
    
}
//---------------------------------------------------------------------------菜单定义及调用ok
int menu()
{
     char *m[9]={"1.Add Record",
                 "2.Del Record",
                 "3.Show All",
                 "4.Search",
                 "5.Change",
                 "6.Add from Text",
                 "7.Write to Text",
                 "8.Sort",
                 "9.Quit"};
     int i;
     char c;
     do
     {
         system("cls");
         cout<<"What do you want:"<<endl;cout<<endl;
         for (i=0;i<9;i++)cout<<m[i]<<endl;
         cout<<"input(1_9):";
         cin>>c;
     }while (c<'0'||c>'9');
     return(c-'0');
}
void work()
{
     for(;;)
     {
         switch(menu())
         {
         case 1:
             cout<<"Please write down the imformation:"<<endl;
             add();
             break;
         case 2:
             cout<<"Please write down the name:"<<endl;
             del();
             break;
         case 3:
             if(s1.gethead())s1.showall();
             else cout<<"No record!"<<endl;
             system("pause");


             break;
         case 4:
             cout<<"Please write down a name:"<<endl;
             find();
             system("pause");
             break;
         case 5:
             cout<<"Please write down a name:"<<endl;
             modify();
             system("pause");
             break;
         case 6:
             cout<<"Please input the text's name:";
             addtxt();
             break;
         case 7:
             cout<<"Please input the text's name:";
             writetxt();
             break;
         case 8:
             addsort();
             system("pause");
             break;
         case 9:
              s1.writelist("data1.txt");
             s1.writelistbin();
             exit(0);
         }
     }
}
//----------------------------------------------------------------------菜单调用结束
//----------------------------------------------------------------------主程序
void main()
{
     s1.creatlist("data.dat");
     work();
}