#include <iostream>
#include <string>
 
const int SONGS = 2;
 
using namespace std;
struct mp3Type
{
    int id;
    string songTitle;
    string artist;
    string length;
    string size;
    mp3Type *link;
};
 
 
void addSong(mp3Type*& first, mp3Type*& last);
void deleteSong(mp3Type*& first);
void modifySong(mp3Type*& first, mp3Type*& last);
void printSong(mp3Type*& first);
 
 
int main()
{
	mp3Type *first, *last;
	char selection;
 
 
	do
	{
         cout<<"a - Add a song "<<endl;
         cout<<"d - Delete a song"<<endl;
         cout<<"m - Modify a song's information "<<endl;
         cout<<"p - Print a list of songs "<<endl;
         cout<<"q - Quit "<<endl;
         cin>>selection;
         switch(selection)
         {
                          case 'a': addSong(first,last);
                               break;
                          case 'd': deleteSong(first);
                               break;
                          case 'm': modifySong(first,last);
                               break;
                          case 'p': printSong(first);
                               break;
                          case 'q': 
                               break;
                          default: cout<<"Invalid option "<<endl;
         }
     }
          while (selection != 'q');
 
 
         	system("PAUSE");
	        return 0;
}
 
void addSong(mp3Type*& first, mp3Type*& last)
{
 
 
    int id;
    char songTitle[100];
    char artist[100];
    string length;
    string size;
    mp3Type *newNode;
    char selection;
 
    first = NULL;
    last = NULL;
 
 
 
        for (int i = 0; i < SONGS; i++)
         {
         cout<<endl;
         cout<<"Adding song # "<<i+1<<endl;
         cout<<endl;
         cout<<"\nSong title: ";
         std::cin.getline(songTitle, 100);
         std::cin.getline(songTitle, 100);
         cout<<"ID: ";
         cin>>id;
         cout<<"Artist: ";
         std::cin.getline(artist, 100);
         std::cin.getline(artist, 100);; 
         cout<<"Length: ";
         cin>>length;
         cout<<"Size: ";
         cin>>size;
 
         newNode = new mp3Type; // create new node
         newNode->songTitle = songTitle;
         newNode->id = id;
         newNode->artist = artist;
         newNode->length = length;
         newNode->size = size;
         newNode->link = NULL;
 
         if (first == NULL)
         {
            first = newNode;
            last = newNode;
         }
         else
         {
           last->link = newNode;
           last = newNode;
         }
         }
 
}
 
void deleteSong(mp3Type*& first)
{
 
  mp3Type *last,*current,*trailcurrent;
  bool found;
  int id;
 
  current = first;
 
  cout<<"Enter song ID that you like to delete"<<endl;
  cout<<endl;
  cin>>id;
 
          for (int i = 0; i < SONGS; i++)
          {   
         if (first->link != NULL)
         {
           current = first->link;
           first->link = first->link->link;
           delete current;
         }
         else
         {
         found = false;
         trailcurrent = first;
         }
         current = first->link;
         }   
 
 
}
 
void modifySong(mp3Type*& first, mp3Type*& last)
{
 
   int id;
   char newsongTitle[100];
   char newartist[100];
   string newlength;
   string newsize;
   bool found = false;
   mp3Type *current;
 
   printSong(first);
 
   current = first;
 
 
   cout<<"Enter the id of the song to modify information"<<endl;
   cin>>id;
 
 
   while (current != NULL)
   {         
    if (current->id == id)
    {
         cout<<endl;
         cout<<"Song title: ";
         std::cin.getline(newsongTitle, 100);
         std::cin.getline(newsongTitle, 100);
         cout<<"Artist: ";
         std::cin.getline(newartist, 100);
         cout<<"Length: ";
         cin>>newlength;
         cout<<"Size: ";
         cin>>newsize;
 
     current->songTitle = newsongTitle;
     current->artist = newartist;
     current->length = newlength;
     current->size = newsize;
    } 
   current = current->link; 
    }
 
}
 
void printSong(mp3Type*& first)
{
 
     cout<<"Printing song list..."<<endl;
     mp3Type *current;
 
 
        current = new mp3Type;
        current = first;    
        while (current != NULL)
        {
          cout<<endl;
          cout<<current-> songTitle <<endl;
          cout<<current-> id <<endl;
          cout<<current-> artist <<endl;
          cout<<current-> length <<endl;
          cout<<current-> size <<endl;
          cout<<endl;
          current = current->link;
        }
 
 
}

get information from user, but ignore it
 
for as many songs as there are in the list
  if list is longer than two 
     delete the second song in the list
  else
     assign a value to a flag but never evaluate the flags value

void deleteSong(mp3Type*& first)
{
 
  mp3Type *last,*current,*trailcurrent;
  bool found;
  int id;
 
  current = first;
 
  cout<<"Enter song ID that you like to delete"<<endl;
  cout<<endl;
  cin>>id;
 
          for (int i = 0; i < SONGS; i++)
          {   
         if (first->link != NULL)
         {
           current = first->link;
           first->link = first->link->link;
           delete current;
         }
         else
         {
         found = false;
         trailcurrent = first;
         }
         current = first->link;
         }   
 
 
}