Question

Program: Playlist (C++)

I'm having difficulty figuring out how to get the header file to work.

You will be building a linked list. Make sure to keep track of both the head and tail nodes.

(1) Create three files to submit.

Playlist.h - Class declaration

Playlist.cpp - Class definition

main.cpp - main() function

Build the PlaylistNode class per the following specifications. Note: Some functions can initially be function stubs (empty functions), to be completed in later steps.

Default constructor (1 pt)

Parameterized constructor (1 pt)

Public member functions

InsertAfter() (1 pt)

SetNext() - Mutator (1 pt)

GetID() - Accessor

GetSongName() - Accessor

GetArtistName() - Accessor

GetSongLength() - Accessor

GetNext() - Accessor

PrintPlaylistNode()

Private data members

string uniqueID - Initialized to "none" in default constructor

string songName - Initialized to "none" in default constructor

string artistName - Initialized to "none" in default constructor

int songLength - Initialized to 0 in default constructor

PlaylistNode* nextNodePtr - Initialized to 0 in default constructor

Ex. of PrintPlaylistNode output:

Unique ID: S123
Song Name: Peg
Artist Name: Steely Dan
Song Length (in seconds): 237

(2) In main(), prompt the user for the title of the playlist. (1 pt)

Ex:

Enter playlist's title: JAMZ 

(3) Implement the PrintMenu() function. PrintMenu() takes the playlist title as a parameter and outputs a menu of options to manipulate the playlist. Each option is represented by a single character. Build and output the menu within the function.

If an invalid character is entered, continue to prompt for a valid choice. Hint: Implement Quit before implementing other options. Call PrintMenu() in the main() function. Continue to execute the menu until the user enters q to Quit. (3 pts)

Ex:

JAMZ PLAYLIST MENU
a - Add song
d - Remove song
c - Change position of song
s - Output songs by specific artist
t - Output total time of playlist (in seconds)
o - Output full playlist
q - Quit

Choose an option:

(4) Implement "Output full playlist" menu option. If the list is empty, output: Playlist is empty (3 pts)

Ex:

JAMZ - OUTPUT FULL PLAYLIST
1.
Unique ID: SD123
Song Name: Peg
Artist Name: Steely Dan
Song Length (in seconds): 237

2.
Unique ID: JJ234
Song Name: All For You
Artist Name: Janet Jackson
Song Length (in seconds): 391

3.
Unique ID: J345
Song Name: Canned Heat
Artist Name: Jamiroquai
Song Length (in seconds): 330

4.
Unique ID: JJ456
Song Name: Black Eagle
Artist Name: Janet Jackson
Song Length (in seconds): 197

5. 
Unique ID: SD567
Song Name: I Got The News
Artist Name: Steely Dan
Song Length (in seconds): 306

(5) Implement the "Add song" menu item. New additions are added to the end of the list. (2 pts)

Ex:

ADD SONG
Enter song's unique ID: SD123
Enter song's name: Peg
Enter artist's name: Steely Dan
Enter song's length (in seconds): 237

(6) Implement the "Remove song" function. Prompt the user for the unique ID of the song to be removed.(4 pts)

Ex:

REMOVE SONG
Enter song's unique ID: JJ234
"All For You" removed

(7) Implement the "Change position of song" menu option. Prompt the user for the current position of the song and the desired new position. Valid new positions are 1 - n (the number of nodes). If the user enters a new position that is less than 1, move the node to the position 1 (the head). If the user enters a new position greater than n, move the node to position n (the tail). 6 cases will be tested:

Moving the head node (1 pt)

Moving the tail node (1 pt)

Moving a node to the head (1 pt)

Moving a node to the tail (1 pt)

Moving a node up the list (1 pt)

Moving a node down the list (1 pt)

Ex:

CHANGE POSITION OF SONG
Enter song's current position: 3
Enter new position for song: 2
"Canned Heat" moved to position 2

(8) Implement the "Output songs by specific artist" menu option. Prompt the user for the artist's name, and output the node's information, starting with the node's current position. (2 pt)

Ex:

OUTPUT SONGS BY SPECIFIC ARTIST
Enter artist's name: Janet Jackson

2.
Unique ID: JJ234
Song Name: All For You
Artist Name: Janet Jackson
Song Length (in seconds): 391

4.
Unique ID: JJ456
Song Name: Black Eagle
Artist Name: Janet Jackson
Song Length (in seconds): 197

(9) Implement the "Output total time of playlist" menu option. Output the sum of the time of the playlist's songs (in seconds). (2 pts)

Ex:

OUTPUT TOTAL TIME OF PLAYLIST (IN SECONDS)
Total time: 1461 seconds

Answer 1

Here is the code.

compile : g++ Playlist.cpp main.cpp

Playlist.h

#ifndef PLAYLIST_H
#define PLAYLIST_H
#include <iostream>
using namespace std;
class PlaylistNode
{
private:
string uniqueID;
string songName;
string artistName;
int songLength;
PlaylistNode* nextNodePtr;
public:
PlaylistNode();
PlaylistNode(string id, string song, string artist, int len);
PlaylistNode* InsertAfter(string id, string song, string artist, int len);
void SetNext(PlaylistNode *next);
string GetID();
string GetSongName();
string GetArtistName();
int GetSongLength();
PlaylistNode* GetNext();
void PrintPlaylistNode();
};
#endif

Playlist.cpp

#include "Playlist.h"
#include <iostream>
using namespace std;
PlaylistNode::PlaylistNode()
{
uniqueID = "none";
songName = "none";
artistName = "none";
songLength = 0;
nextNodePtr = 0;
}

PlaylistNode::PlaylistNode(string id, string song, string artist,int len)
{
uniqueID = id;
songName = song;
artistName = artist;
songLength = len;
nextNodePtr = 0;
}

PlaylistNode* PlaylistNode::InsertAfter(string id, string song, string artist,int len)
{
nextNodePtr=new PlaylistNode(id,song,artist,len);
return nextNodePtr;
}
void PlaylistNode::SetNext(PlaylistNode *next)
{
nextNodePtr = next;
}
string PlaylistNode::GetID()
{
return uniqueID;
}
string PlaylistNode::GetSongName()
{
return songName;
}
string PlaylistNode::GetArtistName()
{
return artistName;
}
int PlaylistNode::GetSongLength()
{
return songLength;
}
PlaylistNode* PlaylistNode::GetNext()
{
return nextNodePtr;
}
void PlaylistNode::PrintPlaylistNode()
{
cout<<"Unique ID: "<<uniqueID<<endl;
cout<<"Song Name: "<<songName<<endl;
cout<<"Artist Name: "<<artistName<<endl;
cout<<"Song Length(in seconds): "<<songLength<<endl;
}

main.cpp

#include "Playlist.h"
#include <iostream>
using namespace std;

void PrintMenu(string listName);
void SongsByArtist(PlaylistNode* head);
void TotalTime(PlaylistNode* head);
void OutputFullList(string listname, PlaylistNode *head);

//all below function take head and tail by reference and modify their values
void AddSong(PlaylistNode* &head, PlaylistNode* &tail);
void RemoveSong(PlaylistNode* &head, PlaylistNode* &tail);
void ChangePosition(PlaylistNode* &head, PlaylistNode* &tail);

int main()
{
string listname;
cout<<"Entr playlist's title: ";
cin>>listname;

PrintMenu(listname);
}

void PrintMenu(string listname)
{
string option;
PlaylistNode *head=0, *tail=0;
while(true)
{
cout<< listname << " PLAYLIST MENU"<<endl;
cout<<"a - Add song"<<endl;
cout<<"d - Remove song"<<endl;
cout<<"c - Change position of song"<<endl;
cout<<"s - Output songs by specific artist"<<endl;
cout<<"t - Output total time of playlist (in seconds)"<<endl;
cout<<"o - Output full playlist"<<endl;
cout<<"q - Quit"<<endl;
cout<<"Enter your choice: ";
cin>>option;
if(option =="A" || option == "a")
{
AddSong(head,tail);
cout<<"Finished adding."<<endl;
}
else if (option == "d" || option =="D")
{
RemoveSong(head, tail);
}
else if(option =="c" || option == "C")
{
ChangePosition(head, tail);
}
else if(option =="s" || option=="S")
{
SongsByArtist(head);
}
else if(option =="t" || option =="T")
{
TotalTime(head);

}
else if(option =="o" || option == "O")
{
OutputFullList(listname,head);
}
else if(option == "q" || option =="Q")
{
break;
}
else
{
cout<<"Invalid menu choice!"<<endl;
}
cout<<endl;
}
}

void OutputFullList(string listname, PlaylistNode *head)
{
int i=1;
PlaylistNode *p=head;
cout<<listname << " - OUTPUT FULL PLAYLIST"<<endl;
while(p != NULL)
{
cout<<i<<"."<<endl;
p->PrintPlaylistNode();
cout<<endl<<endl;
p = p->GetNext();
i++;
}
}

void AddSong(PlaylistNode* &head, PlaylistNode* &tail)
{
string id, song, artist;
int len;
cout<<"ADD SONG"<<endl;
cout<<"Enter song's unique ID: ";
cin>>id;
getchar();
cout<<"Enter songs's name: ";
getline(cin, song);

cout<<"Enter artist's name: ";
getline(cin, artist);
cout<<"Enter song's length(in seconds): ";
cin>>len;
if(tail == 0)
{
head = tail = new PlaylistNode(id,song,artist,len);
}
else
tail=tail->InsertAfter(id, song, artist, len);
}

void RemoveSong(PlaylistNode* &head, PlaylistNode* &tail)
{
string id;
PlaylistNode *p= head, *prev=NULL;
cout<<"REMOVE SONG";
cout<<"Enter song's unique ID: ";
cin>>id;

while(p != NULL)
{
if(p->GetID() == id)
{
if(p == head) // removing head node
{
head = p->GetNext();
if(tail == p) //removing the single node whihc is head ad tail
tail = 0;
}
else
{
prev->SetNext(p->GetNext());
if(tail == p)
tail = prev;
}
cout<<"\"" << p->GetSongName() << "\" removed."<<endl;
delete p;
return;
}
prev = p;
p = p->GetNext();
}
}

void ChangePosition(PlaylistNode* &head, PlaylistNode* &tail)
{
int old_pos, new_pos;
PlaylistNode *p=head, *prev=0, *n;

if(head == tail)
{
cout<<"List has less than 2 elements. Can't change position."<<endl;
return;
}

cout<<"CHANGE POSITION OF SONG"<<endl;
cout<<"Enter song's current position: ";
cin>>old_pos;
cout<<"Enter new position for song: ";
cin>>new_pos;

for(int i=1;p != 0 && i < old_pos; i++)
{

prev = p;
p = p->GetNext();
cout<<p->GetSongName()<<endl;

}

if(p == 0)
return;

if(head == p)
head = p->GetNext();
else
{
prev->SetNext(p->GetNext());
if(tail == p)
tail = prev;
}

p->SetNext(0);
n = p;

p = head;
prev = 0;

//new_pos--;//reduce the location by 1 since we have removed 1 node

for(int i=1; p != 0 && i< new_pos; i++)
{
prev = p;
p = p->GetNext();
}

if(prev == 0)
{
n->SetNext(head);
head = n;
}
else
{
n->SetNext(prev->GetNext());
prev->SetNext(n);
if(tail == prev)
tail = n;
}

}

void SongsByArtist(PlaylistNode *head)
{
int pos = 1;
string name;
PlaylistNode *p=head;

cout<<"OUTPUT SONGS BY SPECIFIC ARTIST"<<endl;
getchar();
cout<<"Enter artist's name: ";
getline(cin, name);
while(p != 0)
{
if(p->GetArtistName() == name)
{
cout<<pos<<"."<<endl;
p->PrintPlaylistNode();
}

p = p->GetNext();
pos++;

}

}

void TotalTime(PlaylistNode *head)
{
int total = 0;
PlaylistNode *p=head;
cout<<"OUTPUT TOTAL TIME OF PLAYLIST (IN SECONDS)";
while(p != 0)
{
total += p->GetSongLength();
p = p->GetNext();
}
cout<<"Total time: "<<total<<" seconds "<<endl;

}