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Linked List Issues:

jocdrew21 (8)
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#ifndef __addressList__
#define __addressList__

#include <iostream>
#include <string>

using namespace std;
typedef struct node {
    string Name;
    string DOB;
    string address;
    string aniversary;
    node *next;
} *nodePtr;

class AddressBook {
private:
    nodePtr head;
    nodePtr current;
    nodePtr temp;
    
public:
    AddressBook();
    
    void userPromptStatement();
    void AddNode(nodePtr);
    void deleteName(string);
    void EditNameOrDate();
    void PrintAddressBook();
    void GenBirthdayCards(string);
    void GenAnnCard(string);
    void ExitProgram();
    
};

#endif 

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#include <iostream>
#include <string>
#include "addressList.h"
using namespace std;
AddressBook::AddressBook(){
    
    head=NULL;
    current=NULL;
    temp=NULL;
    
}

void setAniversary(string);
string getAniversary();
void AddressBook::AddNode(nodePtr temp)
{
    if (head != NULL) { //list is already made
        current = head; //makes current pointer point to head of the list
        
        while (current->next != NULL)
        {   //while the next of current is not at end
            current = current->next;     //advance to next node
        }
        
        current->next =new node;
        current->next->address=temp->address;
        current->next->aniversary=temp->aniversary;
        current->next->DOB=temp->DOB;
        current->next->Name=temp->Name;
        current->next->next=nullptr;
    }
    else
    {
        head = new node; //now head is the front of the list
		head->address=temp->address;
		head->aniversary=temp->aniversary;
		head->DOB=temp->aniversary;
		head->Name=temp->Name;
		head->next=nullptr;
    }
    
}

void AddressBook::deleteName(string Delname)
{
    //nodePtr delPtr = NULL;
    temp = head;
    current=head;
    
	while (current != NULL && current->Name != Delname)
	{
        temp = current;
        current=current->next;
    }
    if (current == NULL) {
        cout<<Delname<<"Was not in the list\n";
    }
    else{
		temp->next=current->next;
        delete current;
        cout<<"Name: "<< Delname <<" was deleted.\n";
    }
    
}

void AddressBook::PrintAddressBook()
{
    current = head;
	if (current==nullptr) cout<<"The list is empty\n";
    while (current != NULL) {
        cout<<"NAME: "<<current->Name<<endl;
        cout<<"ADDRESS: "<<current->address<<endl;
		cout<<"BIRTHDAY: "<<current->DOB<<endl;
        cout<<"ANNIVERSARY: "<<current->aniversary<<endl;
        cout<<"\n";
        current= current->next;
    }
    
    
}
void AddressBook::EditNameOrDate()
{
	cout<<"1. Edit Name: \n";
	cout<<"2. Edit Birthday: \n";
    cout<<"3. Edit Anniversary: \n";
	int input;
	cin>>input;
    
	if (input==1)
	{
		cout<<"Enter the name you want to edit: /n";
        nodePtr curr = head;
        
        if (curr==NULL) {
            cout<<"Error, list is empty"<<endl;
        }
        string name;
        name.clear();
		getline(cin,name,'\n');
        
		while(curr->next!= NULL && curr->next->Name != name)
		{
			curr=curr->next;
		}
        
		cout<<"The current name is: "<<curr->next->Name<<endl;
		cout<<"Enter the new name: "<<name;
		curr->next->Name=name;
		cout<<"The name has been successfully changed to "<<curr->next->Name<<endl;
        
        }
	
	else if (input==2)
	{
        cout<<"Enter the Birthday you want to edit: ";
		string date;
		getline(cin,date,'\n');
		nodePtr curr=head;
		while(curr->next!=NULL && curr->next->DOB!=date)
		{
			curr=curr->next;
		}
		cout<<"The current name is: "<<curr->next->DOB<<endl;
		cout<<"Enter the new name: "<<date;
		curr->next->DOB=date;
		cout<<"The name has been successfully changed to "<<curr->next->DOB<<endl;
    
	}
    else if (input==3)
	{
        cout<<"Enter the Anniversary date you want to edit: ";
		string AnnDate;
		getline(cin,AnnDate,'\n');
		nodePtr curr=head;
		while(curr->next!=NULL && curr->next->aniversary!=AnnDate)
		{
			curr=curr->next;
		}
		cout<<"The current name is: "<<curr->next->aniversary<<endl;
		cout<<"Enter the new name: "<<AnnDate;
		curr->next->aniversary=AnnDate;
		cout<<"The name has been successfully changed to "<<curr->next->aniversary<<endl;
        
	}
}
void AddressBook::GenBirthdayCards(string birthdayBoy)
{
    cout<<"Dear "<<birthdayBoy<<"\n\n";
    
    cout<<"Hope your birthday is really wonderful and this coming year is the best yet!\n";
    cout<<endl<<endl;
    cout<<"Love,\n";
    cout<<"Joanne\n";
    
}

void AddressBook::GenAnnCard(string happyCouple)
{
    cout<<"Dear "<<happyCouple<<endl;
    cout<<endl<<endl;
    cout<<"May your anniversary be the best yet and we wish you more to come\n";
    cout<<endl<<endl;
    cout<<"Love,\n";
    cout<<"Joanna\n";
    
}
void AddressBook::userPromptStatement()
{
    cout<<"Enter 1 to add a new contact"<<endl;
    cout<<"Enter 2 to delete a contect"<<endl;
    cout<<"Enter 3 edit a contect"<<endl;
    cout<<"Enter 4 to print your address book"<<endl;
    cout<<"Enter 5 to generate birthday cards"<<endl;
    cout<<"Enter 6 to generate anniversary cards"<<endl;
    cout<<"Enter 7 to exit the program"<<endl;
    
}

void AddressBook::ExitProgram()
{
    
    EXIT_SUCCESS;
    
}

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#include <iostream>
#include <string>
#include "addressList.h"

using namespace std;


int main()
{
    
    AddressBook MyAddressBook;
    int userInput;
    //string NAME, BIRTHDAY, ADDY, NEWANIVERSARY;
	nodePtr temp=new node;
    MyAddressBook.userPromptStatement();
	string NAME;
	while(1)
	{
		cin>>userInput;
        
		switch (userInput) {
			case 1:
				cout<<"NAME: ";
				cin.ignore();
				getline(cin,temp->Name,'\n');
				cout<<"\nBIRTHDAY: ";
				getline(cin,temp->DOB,'\n');
				cout<<"\nADDRESS: ";
				getline(cin,temp->address,'\n');
				cout<<"\nANIVERSARY DATE: ";
				getline(cin,temp->aniversary,'\n');
				MyAddressBook.AddNode(temp);
				MyAddressBook.userPromptStatement();
				break;
			case 2:
				cout<<"Which contact would you like to delete?\n";
				cin>>NAME;
                
				MyAddressBook.deleteName(NAME);
				MyAddressBook.userPromptStatement();
				break;
			case 3:
				MyAddressBook.EditNameOrDate();  //need help here
				break;
			case 4:
				MyAddressBook.PrintAddressBook();
				MyAddressBook.userPromptStatement();
				break;
            case 5:
				cout<<"Who would you like to send a Birthday card too?\n";
				cin>>NAME;
				MyAddressBook.GenBirthdayCards(NAME);
				MyAddressBook.userPromptStatement();
				break;
            case 6:
				cout<<"Who would you like to send a anniversary card too?\n";
				cin>>NAME;
				MyAddressBook.GenAnnCard(NAME);
				MyAddressBook.userPromptStatement();
				break;
                
            case 7:
				MyAddressBook.ExitProgram();
				break;
			default:
				break;
		}
	}
    return 0;
}

The errors are:
Lets say I enter Number 3 to edit a contact line 99 comes up with an error "Thread 1: EXE_BAD_ACCESS (code=1,address=0x60)". I do not even know what that means.

Delete Contact also is giving me errors. I am can't seem to see the error. The while loop on 99, 114, 130. I get the following error when I try to delete a name:
Linked Lists(5607,0x7fff73e1d310) malloc: *** error for object 0x100103b40: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug
Last edited on
Zhuge (4664)
Try using a debugger to see the status of variables and such when the errors occur.
jocdrew21 (8)
I did but something is not clicking. I put the errors above. It seems to be skipping line 99 when I try to edit a name. I thought something was stored in there so I cleared it. However it jump right to the while loop and fails. This has be puzzled.
ne555 (10692)
http://www.cplusplus.com/forum/general/112111/

Your searches in EditNameOrDate() bypass the first element

Also, you should limit the scope of your variables. There is no good reason for `temp' and `current' to be members of the class.

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		head = new node; //now head is the front of the list
		head->address=temp->address;
		head->aniversary=temp->aniversary;
		head->DOB=temp->aniversary; //¿ever heard of a copy constructor? it would avoid these kind of mistakes
		head->Name=temp->Name;
		head->next=nullptr;
Last edited on
jocdrew21 (8)
I used temp because I was planning on using it as that, temporary and deleting it.
Are you saying my issue is actually in the .h file when I used:
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nodePtr head;
    nodePtr current;
    nodePtr temp;


Now I am starting to get very confused. I did use a constructor:
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AddressBook::AddressBook(){
    
    head=NULL;
    current=NULL;
    temp=NULL;
    
}


Why not make temp and current apart of the class? I need them for when I delete something so that I can attach the list again.
Last edited on
ne555 (10692)
When you need it, create it. It's a lot easier than trying to maintain the invariant. (it would be like using global variables)


> Are you saying my issue is actually in the .h file when I used:
No, I'm saying that that's bad design.


You've got an issue with your searches
while(curr->next!=NULL && curr->next->DOB!=date) may end because `cur->next' is NULL, and later you dereference it.
jocdrew21 (8)
OK I see what you are saying.... How would you design it?
ne555 (10692)
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struct node{
    string Name;
    string DOB;
    string address;
    string aniversary;
    //node *next;
};

class AddressBook {
private:
   std::list<node> list; //or another container


If you question was about how to design the linked list, I would use an empty header cell (no pointer) and make it circular, so all the pointers point to a cell and there is no need to threat `header' different.

But your approach works too, simply limit the scope of your variables.


You need to check at the start of the search
- if `head' is NULL
- if `head' has the element that you are searching for

Then you need to consider the case where the search fails (`curr->next' is NULL)
Largins7 (14)
Only a few changes here. I removed the string arguments to the methods that had then as the temp node can be used for that
I added an initialize method, a ProcessInput method and a destructor. I also capitalized several names for consistency.

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#ifndef __addressList__
#define __addressList__

#include <iostream>
#include <string>
#include <cstdlib>

using namespace std;

class AddressBook
{
private:
  typedef struct node {
    string Name;
    string DOB;
    string Address;
    string Aniversary;
    struct node *next;
  } *nodePtr;

  nodePtr head;
  nodePtr current;
  nodePtr temp;

  void AddNode(nodePtr);
  void DeleteName();
  void EditNameOrDate();
  void PrintAddressBook();
  void GenBirthdayCards();
  void GenAnnCard();
  void ExitProgram();
public:
  AddressBook();

  void Initialize();
  void ProcessInput();
  void UserPromptStatement();
  ~AddressBook();
};

#endif // __addressList__


The main method has been simplified and the user input placed in a ProcessInput file (and method)

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#include "AddressList.h"

using namespace std;

int main()
{
  AddressBook AdrBk;

  AdrBk.Initialize();
  AdrBk.ProcessInput();
}

AddressBook::AddressBook()
{
  // Create class object
}

AddressBook::~AddressBook()
{
  // Delete class object
  delete temp;
}

void AddressBook::ExitProgram()
{
  EXIT_SUCCESS;
}


The AddNode method has been simplified somewhat

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#include "AddressList.h"

void AddressBook::AddNode(nodePtr current)
{
  nodePtr hold = new node;

  current = NULL;
  if(head) {
    current = head;
    while(current)
    {
      hold = current;
      current = current->next;
    }
    current = hold->next = new node;
  } else {
    current = head = new node;
  }
  current->next = NULL;

  current->Address = temp->Address;
  current->Aniversary = temp->Aniversary;
  current->DOB = temp->DOB;
  current->Name = temp->Name;
}


You forgot to update the next link of the node just before the one deleted, I added that in the delete name method

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include "AddressList.h"

void AddressBook::DeleteName()
{
  nodePtr Hold = new node;
  Hold = head;

  if(head) {
    current = head;
    while(current) {
      if(current->Name == temp->Name) {
          Hold->next = current->next;
          delete current;
          cout<<"Name: "<< temp->Name <<" was deleted.\n";
          break;
      }
      Hold = current;
      current = current->next;
    }
  }
  if(head == NULL || current == NULL)
    cout<<temp->Name<<"Was not in the list\n";
}


The Initialize method
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#include "AddressList.h"

void AddressBook::Initialize()
{
  temp = new node;
  head = NULL;
  current = NULL;
}


ProcessInput Looks pretty much the same except for the removal of string arguments

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#include "AddressList.h"

void AddressBook::ProcessInput()
{
  string NAME;
  int userInput;

	while(1)
	{
		cin>>userInput;

		switch (userInput) {
			case 1:
				cout<<"NAME: ";
				cin.ignore();
				getline(cin,temp->Name,'\n');
				cout<<"\nBIRTHDAY: ";
				getline(cin,temp->DOB,'\n');
				cout<<"\nADDRESS: ";
				getline(cin,temp->Address,'\n');
				cout<<"\nANIVERSARY DATE: ";
				getline(cin,temp->Aniversary,'\n');
				AddNode(temp);
				UserPromptStatement();
				break;
			case 2:
				cout<<"Which contact would you like to delete?\n";
				getline(cin,temp->Name,'\n');
				DeleteName();
				UserPromptStatement();
				break;
			case 3:
				EditNameOrDate();  //need help here
				break;
			case 4:
				PrintAddressBook();
				UserPromptStatement();
				break;
      case 5:
				cout<<"Who would you like to send a Birthday card too?\n";
				getline(cin,temp->Name,'\n');
				GenBirthdayCards();
				UserPromptStatement();
				break;
      case 6:
				cout<<"Who would you like to send a anniversary card too?\n";
				getline(cin,temp->Name,'\n');
				GenAnnCard();
				UserPromptStatement();
				break;
      case 7:
				ExitProgram();
				break;
			default:
				break;
		}
	}
}


Get Annaversary cards would look like

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#include "AddressList.h"

void AddressBook::GenAnnCard()
{
  current = head;
  while(current && (current->Name != temp->Name) && (current->Aniversary != temp->Aniversary)) {
      current++;
  }
  if(current) {
    cout<<"Dear "<<temp->Name<<endl;
    cout<<endl<<endl;
    cout<<"May your anniversary be the best yet and we wish you more to come\n";
    cout<<endl<<endl;
    cout<<"Love,\n";
    cout<<"Joanna\n";
  }
}


The other functions basicaly the same.

You still have the situation where there will be identical names. I suggest that you add a 16 bit hash code to your node typedef. the structure is so small that woud could add all fields ti get a unique code.
When searching for a particular person, you could bring up the names and street where they lived and have the user select the proper one.

Hope ypu find this helpful.

Largins
jocdrew21 (8)
Largin:
Thank you very much. Some of your methods look cleaner then mine. I forgot all about a destructor too so thanks again. I also like how to put the struct in the class and not global. I suppose that is a better way, and safer. How you did the generation of the cards was a nice touch. I had to double take for a second when I looked at it. I am going to do some more work on this program but using <list> has me intrigued and confused.

ne555:
I have never really worked with <list> before besides pushing a data into it and iterating through it to print it off. Would I just need the list like you wrote it and head in the private and have head equal the list? I started to look into that way and found more questions. Could you clear this up or me?

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