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#include <iostream.h>
#include <stdlib.h>

int getdata();

struct structlist{
 structlist *previous;
 int data;
};

class classlist{
  structlist *current;
 public:
  classlist(int);
  classlist(const classlist &);
  int operator [] (int);
  int operator - (const classlist &);
};

int classlist::operator - (const classlist &original){





};

int classlist::operator [] (int num){
 for(structlist *newlist = current;\
   (--num)&&(newlist); newlist = newlist->previous) ;
 return (newlist)?newlist->data:-1;
}


classlist::classlist(const classlist &original){

 cout<<"\n++++++++++++++++++++++++++++++++++++++++\n"<< \
  "Creating a copy-list :";

 structlist *current = new structlist;

 structlist *temp = new structlist;
 temp = original.current;

 current->data = temp->data;
 current->previous = NULL;
 temp = temp->previous;
 while(temp){
  structlist *newlist = new structlist;
  newlist->data = temp->data;
  newlist->previous = current;
  cout<<"\n\nDeBug:"<<current->data;
  current = newlist;
  temp = temp->previous;
 }
  cout<<"\n\nDeBug:"<<current->data;
/*

 while(current){
  cout<<"\nCopy list Data : "<<current->data;
  current = current->previous;
 }
*/
 cout<<"\nDone\n";
}


classlist::classlist(int num){

  cout<<"\n++++++++++++++++++++++++++++++++++++++++++++++++"<<\
    "\nCreating LIST of "<<num<<" elements :";

  current->data = num;
  cout<<"\nNUM+:"<<num;
  current->previous = NULL;
  while(--num){
    structlist *newlist = new structlist;
    newlist->data = num;
    cout<<"\nNUM+:"<<num;
    newlist->previous = current;
    current = newlist;
  }

  cout<<"\nDone\n";

/*
  cout<<"\n++++++++++++++++++++++++++++++++++++++++++++++++"<<\
    "\nReading from excisting LIST elements :";

  while(current){
   cout<<"\nNUM-:"<<current->data;
   current = current->previous;
  }

  cout<<"\nDone\n";
*/

}


void main(){
 classlist list = 4;
 classlist copylist = list;
 cout<<"\nElement: "<<list[3];
}