Thread: Linked list probs

Hey all,
I'm including my telephone linked list code.
I am having major problems trying to insert (or add)
my new node in the appropriate alphabetical order.
I tried to overload the > op to compare
the first letters of the names -enterd last,first.
but i keep crashing when the print function calls.
(I know the menu can look better, I am just trying to get func-tionality down first).
I suspect what I am trying to do by inserting alphabetically
will also have something to do with my searchfor function?
any comment on that would be helpful.
thanks very much!
Michele

Code:

#include<iostream>
using namespace std;
 
 
#define MAX  40

struct TeleEntry
{
 
 char EntryName[40];
 char EntryNumber[40];
 bool TeleEntry::operator > (const char* &TeleEntryA) const
 {
     if (strcmp(this->EntryName, TeleEntryA) > 0)
     {return true;}
     else
     {return false;}
 }
 
 TeleEntry* Next;




};
 

class ListofTeles
{
 
public:

 ListofTeles();
 int count();
 TeleEntry* Head;
 

 int Add(TeleEntry* Item);
 TeleEntry *Retrieve(int pos);
 bool Delete();
 bool Delete(int pos);
 void Print();


private:
 
 int size;
};
 
 
 
 
 

//constructor__________________________________
 
ListofTeles::ListofTeles():size(0), Head(NULL)
{
}
 
//initialize count by size_____________________
 
int ListofTeles::count()
{
 return size;
}
 
//ADD_____________________________________________
 
int ListofTeles::Add(TeleEntry *NewItem)
{

 TeleEntry *Sample = new TeleEntry;
 Sample   = NewItem;

 if (Head==NULL)
 {
 Head  = Sample;
 }//if
 else
 {
     while((Sample->EntryName) > (Head->EntryName))
 {
             Head = Sample->Next;
     }//while

              Head  = Sample;
        
            
 }
 return size++;
}//add
 
//ITEM RETRIEVAL__________________________________
 
TeleEntry *ListofTeles::Retrieve(int Position)
{
 
 TeleEntry *Current = Head;
 for (int i=0; i<Position && Current !=NULL; i++)
 {
  Current=Current->Next;
 }
 
 return Current;
 

}
 
//ITEM DELETION______________________________________
 

bool ListofTeles::Delete()
{
 if (Head == NULL)
 {
  std::cout<<"The list is empty\n"<< endl;
  return false;
  
 }
 else
 {
  TeleEntry *Current;
  Current = Head->Next;
  Head->Next=Current->Next;
  size--;
  return true;
 }
  
}
 
//ITEM DELETION WITH ARGUEMENT__________________________
 
bool ListofTeles::Delete(int position)
{
 if (Retrieve(position) == NULL)
  return false;
 else
 {
  Retrieve(position -1)->Next = Retrieve (position +1);
  size--;
  return true;
 }
  
}
//PRINT LIST
void ListofTeles::Print()
{

 cout << "Print Telephone List" << endl;
 
 if (Head == NULL)
 {
  std::cout<<"The list is empty\n"<< endl;
 }
else
{
TeleEntry *Current;

Current = Head;

while (Head!=NULL)
{

  cout<<"\nName:     "<<Current->EntryName << "  " <<"Tele #:   "<< Current->EntryNumber << endl;;

  Current = Current->Next;
  Head = Current;

        }//while
    }//else
}//Print
 
//___________________________________________________
 
int main()
{
 
 ListofTeles *Teles= new ListofTeles();
 
 TeleEntry     *Tele;

 char Name [MAX];
 char Number[MAX];
 bool b;

 cout << "would you like to enter a name/number?"<< endl;
 cout << "enter 1 for yes 0 for no" << endl;
 cin >> b;
 

 while(b==1){
cout << "Enter Name (Last,First) :"<< endl;
cin >> Name;
cout << "Enter Number :"<< endl;
cin >> Number;

 Tele = new TeleEntry;
 strcpy (Tele->EntryNumber, Number);
 strcpy (Tele->EntryName, Name);
 
 Teles->Add(Tele);

 cout << "would you like to enter a name/number?"<< endl;
 cout << "enter 1 for yes 0 for no" << endl;
 cin >> b;

 }

 
cout<<"Qty Telephone Numbers: " << Teles->count() << endl;


Teles->Print();
 
 



 
 


return 0;
 
}