课堂练习 多态性

#include<iostream>

#include<string>

using namespace std;

class Student

{

public:

        virtualvoid get()=0;

        virtualvoid display()=0;

        stringname;

        stringnum;

};

class UnderGrad :public Student

{

public:

      voidget()

        {

               cout<< "姓名:"; cin >> name;

              cout<< "学号:"; cin >> num;

               cout<< "班级号："; cin >> classnum;

        }

  voiddisplay();

private:

        stringclassnum;

};

class Graduate :public Student

{

public:

       voidget()

      {

            cout<< "姓名:"; cin >> name;

            cout<< "学号:"; cin >> num;

            cout<< "导师姓名:"; cin >> tutor;

     }

  voiddisplay();

private:

    stringtutor;

};

void UnderGrad::display()

{

 cout << "姓名"<<"\t"<<"学号"<<"\t"<<"班级"<<endl;

cout<<name<<"\t"<<num<<"\t"<<classnum<<endl;

}

void Graduate::display()

{

 cout << "姓名"<<"\t"<<"学号"<<"\t"<<"导师姓名"<<endl;

  cout<<name<<"\t"<<num<<"\t"<<tutor<<endl;

}

template <typename T>

class SList;

template <typename T>

class Node

{

      friendclass SList<T>;

public:

     Node(T*data) :data(data), next(NULL){}

private:

   T*data;

  Node<T>*next;

};

template < typename T>

class SList

{

public:

     SList():head(NULL),tail(NULL){}

      voidInsert(T *newNode)

      {       

              Node<T>*t = new Node<T>(newNode);         

            if(!head) 

           {                

              head= tail = t;          

                length++;

          }       

              else 

                {       

                       tail->next= t;           

                 tail= t;            

              length++;         

             }

    }

   voidDelete()

     {       

             Node<T>*t = head;         

           head= head->next;

         deletet;

      }

    voidPrint()

        {       

                  if(!head) 

                {                

                        cout<< "链表空..." << endl;           

                         return;                    

                  }

                  Node<T>*t;    

                for(t = head; t; t = t->next)     

            {                

                   t->data->display();  

                 }     

 }

private:

        intlength;

        Node<T>*head;

       Node<T>*tail;

};

int main()

{

        charc; UnderGrad U; Graduate G;

        SList<Student>List;

        for(;;)

        {

                  cout<< "创建学生:类型（U）本科生,（G）研究生,（E）结束：";

                  cin>> c;

                  if(c == 'E'){ cout << "销毁链表."<<endl; break; }

                  elseif (c == 'U' || c == 'G')

                           switch(c)

                           {

                           case'U':U.get(); List.Insert(&U); break;

                           case'G':G.get(); List.Insert(&G); break;

                           default:break;

                           }                

                  elsecout << "输入无效请重新输入:" << endl;

        }

        List.Print();

        List.Delete();

        List.Delete();

        return0;

}