temlist2.cpp

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// temlist2.cpp
// implements linked list as a template
// demonstrates list used with employee class
#include <iostream>
using namespace std;

const int LEN = 80;           //maximum length of names
////////////////////////////////////////////////////////////////
class employee                        //employee class
   {
   private:
      char name[LEN];                 //employee name
      unsigned long number;           //employee number
   public:
      friend istream& operator >> (istream& s, employee& e);
      friend ostream& operator << (ostream& s, employee& e);
   };
//--------------------------------------------------------------
istream& operator >> (istream& s, employee& e)
   {
   cout << "\n   Enter last name: "; cin >> e.name;
   cout << "   Enter number: ";      cin >> e.number;
   return s;
   }
//--------------------------------------------------------------
ostream& operator << (ostream& s, employee& e)
   {
   cout << "\n   Name: " << e.name;
   cout << "\n   Number: " << e.number;
   return s;
   }
////////////////////////////////////////////////////////////////
template<class TYPE>                  //struct "link<TYPE>"
struct link                           //one element of list
   {
   TYPE data;                         //data item
   link* next;                        //pointer to next link
   };
////////////////////////////////////////////////////////////////
template<class TYPE>                  //class "linklist<TYPE>"
class linklist                        //a list of links
   {
   private:
      link<TYPE>* first;              //pointer to first link
   public:
      linklist()                      //no-argument constructor
         { first = NULL; }            //no first link
      void additem(TYPE d);           //add data item (one link)
      void display();                 //display all links
   };
//--------------------------------------------------------------
template<class TYPE>
void linklist<TYPE>::additem(TYPE d)  //add data item
   {
   link<TYPE>* newlink = new link<TYPE>;  //make a new link
   newlink->data = d;                 //give it data
   newlink->next = first;             //it points to next link
   first = newlink;                   //now first points to this
   }
//--------------------------------------------------------------
template<class TYPE>
void linklist<TYPE>::display()        //display all links
   {
   link<TYPE>* current = first;       //set ptr to first link
   while( current != NULL )           //quit on last link
      {
      cout << endl << current->data;  //display data
      current = current->next;        //move to next link
      }
   }
////////////////////////////////////////////////////////////////
int main()
   {                          //lemp is object of
   linklist<employee> lemp;   //class "linklist<employee>"
   employee emptemp;          //temporary employee storage
   char ans;                  //user's response ('y' or 'n')

   do
      {
      cin >> emptemp;         //get employee data from user
      lemp.additem(emptemp);  //add it to linked list lemp
      cout << "\nAdd another (y/n)? ";
      cin >> ans;
      } while(ans != 'n');    //when user is done,
   lemp.display();            //display entire linked list
   cout << endl;
   return 0;
   }