overloading my brain

[dmegee]

Ok here's the deal I need to make a program that runs in this manner...
I have the majority of it done but I have some errors when I try to compile it.
Can anyone help me?

Create a class called Book, which has the following attributes:
1. title(string)
2. publisher (string)
3.Number of pages (int)
These should only be accesible through methods of the book class
then write two constructors for the book class
- a default constructor that sets the title and pulisher to some default value and the number of pages to zero
-an overloaded constructor that takes in three parameters and sets the title, publisher and number of pages appropriately.

I need to write one set method and one get method for each of the attributes of the book class.

finally overload the << so that a book object gets output in the following way:
TITLE: title
PUBLISHER: publisher
NUMBER OF PAGES: number of pages

then I create a class library. this has one attribute: a vector of books that will hold all the books in the library.

I write these member functions for the library class:
bool contains(string title)
void addbook(Book b)
void readfile(string filename)
then after I have defined those member functions I need to overload the following operators :
+=, to add a book to the library (maybe reuse addbook?)
==, to check if a book is in the library ( maybe reuse contains?)
<<,to output all the Books in the library( remember I have already defined this to output a single book)

So basically the program needs to be able to:
1. Read information about books from a file and add the books to the library's collection.
2.Search to see if a book is in the library
3.add a book to the library
4. list all the books in the library, with the publishers and number of pages

This is the code that I have so far, and I'm stuck. I need help on what is commented out and on the main function:


#include <iostream> //Basic Library of terms used by C++
#include <fstream> //Allows the program to read to and from files (I/O)
#include <string> //Allows the program to read strings
#include <vector> //Allows the use of vectors
#include <cctype>
#include <cstdlib>


using namespace std;

class Book //Class called Book
{
private: //private member variables
string title;
string publisher;
int numpages;

public:
friend void operator <<(ostream&, Book);
Book(){ title = ""; publisher = ""; numpages = 0;}
Book(string, string, int);
void set_title(string t) {title = t;}
void set_publisher(string p) {publisher = p;}
void set_numpages(int n){numpages = n;}
string get_title(){ return title;}
string get_publisher(){ return publisher;}
int get_numpages(){return numpages;}
};

class Library
{
public:
friend Library operator +=(Library, Book);
friend bool operator ==(Library, Library);
friend void operator <<(ostream&, Library);
bool contains(string);
void addBook(Book);
void readfile(string);
int size();
Book getBook(int);
private:
vector<Book> book_vector;
};

Book::Book(string new_title, string new_publisher, int new_numpages)
{
set_title(new_title);
set_publisher(new_publisher);
set_numpages(new_numpages);
}


void operator <<(ostream& outs, Book somebook)
{
outs << somebook.get_title() << endl ;
outs << somebook.get_publisher() << endl;
outs << somebook.get_numpages() << endl;
}


bool Library::contains(string test_title)
{
for (int i=0; i < book_vector.size() ; i++)
{
if (test_title == book_vector[i].get_title())
return 1;
}
return 0;
}


void Library::addBook(Book new_Book)
{
book_vector.push_back(new_Book);
}

void Library::readfile(string filename)
{
ifstream ifile;
ifile.open(filename.c_str());
string temptitle;
string temppublisher;
int temppages;
while(!ifile.eof())
{
/* filename >> temptitle;
filename >> temppublisher;
filename >> temppages;*/
Book tempbook(temptitle, temppublisher, temppages) ;
addBook(tempbook);
}
}


int Library::size()
{
return book_vector.size();
}

Library operator +=(Library oldlibrary, Book newbook)
{
oldlibrary.addBook(newbook);
return oldlibrary;
}

Book Library::getBook(int position)
{
return book_vector[position];
}

bool operator ==(Library a, Library b)
{
Book temp_book;
string temp_title;
if(a.size() != b.size())
return 0;
else
for (int i=0; i < a.size() ; i++)
{
temp_book=a.getBook(i);
temp_title=temp_book.get_title();
if (!b.contains(temp_title))
return 0;
}
return 1;

}

void operator <<(ostream& outs, Library temp_library)
{
for (int i=0; i << temp_library.size(); i++)
{
outs << temp_library.getBook(i) ;
}
}


int main()
{
/* char selection;
string filename;
cout<<"Welcome to Dave's woodworking library!"<<endl; //Intro
cout<<"Where everyone is getting hammered or nailed!"<<endl;
cout<<""<<endl;
cout<<"Please make your selction from the list below..."<<endl; //Asks user for input
cout<<"1. Read information about books from a file"<<endl;
cout<<"2. Find a book in the library"<<endl;
cout<<"3. Add your book to our library"<<endl;
cout<<"4. Print out the library's book collection"<<endl;
cout<<"5. Quit the program"<<endl; //Quits the program
cin>> selection;

switch(selection)
do{
case '1':
cout<< "Please enter your filename" <<endl;
cin>> filename;
getline
//read_info_books_file(filename);
break;

case '2':
cout<< "Please enter the name of your book"<<endl;
//cin>> title;
//getline

break;

case '3':
cout<<"Please enter the title, publisher and number of pages"<<endl;
//cin>> title,publisher,numberofpages;
//getline
//add to library
break;

case '4':
//prints out the library's book collection
break;

case '5':
cout<<"Please don't leave us! The books come alive at night!"<<endl;
break;

default:
cout<<"That's not a possible choice...you must have wood for brains!"<<endl;
}while (selection !=4);

*/
}

[willakawill]

switch(selection)
do{
case '1':
cout<< "Please enter your filename" <<endl;
cin>> filename;
getline
//read_info_books_file(filename);
break;

case '2':
cout<< "Please enter the name of your book"<<endl;
//cin>> title;
//getline

break;

case '3':
cout<<"Please enter the title, publisher and number of pages"<<endl;
//cin>> title,publisher,numberofpages;
//getline
//add to library
break;

case '4':
//prints out the library's book collection
break;

case '5':
cout<<"Please don't leave us! The books come alive at night!"<<endl;
break;

default:
cout<<"That's not a possible choice...you must have wood for brains!"<<endl;
}while (selection !=4);

*/
}

You have created an endless loop within the switch statement for any entry of 6 or above

[dmegee]

Well...This is what I have done and I'm not sure that it's right...could someone look over this and give me some answers? The compiler errors are at the bottom. sorry I don't know how to put my code in nice little boxes


#include <iostream> //Basic Library of terms used by C++
#include <fstream> //Allows the program to read to and from files (I/O)
#include <string> //Allows the program to read strings
#include <vector> //Allows the use of vectors
#include <cctype>
#include <cstdlib>


using namespace std;

class Book //Class called Book
{
private: //private member variables
string title;
string publisher;
int numpages;

public:
friend void operator <<(ostream&, Book);
Book(){ title = ""; publisher = ""; numpages = 0;}
Book(string, string, int);
void set_title(string t) {title = t;}
void set_publisher(string p) {publisher = p;}
void set_numpages(int n){numpages = n;}
string get_title(){ return title;}
string get_publisher(){ return publisher;}
int get_numpages(){return numpages;}
};

class Library
{
public:
friend Library operator +=(Library, Book);
friend bool operator ==(Library, Library);
friend void operator <<(ostream&, Library);
bool contains(string);
void addBook(Book);
void readfile(string);
int size();
Book getBook(int);
private:
vector<Book> book_vector;
};

Book::Book(string new_title, string new_publisher, int new_numpages)
{
set_title(new_title);
set_publisher(new_publisher);
set_numpages(new_numpages);
}


void operator <<(ostream& outs, Book somebook)
{
outs << somebook.get_title() << endl ;
outs << somebook.get_publisher() << endl;
outs << somebook.get_numpages() << endl;
}


bool Library::contains(string test_title)
{
for (int i=0; i < book_vector.size() ; i++)
{
if (test_title == book_vector[i].get_title())
return 1;
}
return 0;
}


void Library::addBook(Book new_Book)
{
book_vector.push_back(new_Book);
}

void Library::readfile(string filename)
{
ifstream ifile;
ifile.open(filename.c_str());
string temptitle;
string temppublisher;
int temppages;
while(!ifile.eof())
{
ifile >> temptitle;
ifile >> temppublisher;
ifile >> temppages;
Book tempbook(temptitle, temppublisher, temppages) ;
addBook(tempbook);
}
}


int Library::size()
{
return book_vector.size();
}

Library operator +=(Library oldlibrary, Book newbook)
{
oldlibrary.addBook(newbook);
return oldlibrary;
}

Book Library::getBook(int position)
{
return book_vector[position];
}

bool operator ==(Library a, Library b)
{
Book temp_book;
string temp_title;
if(a.size() != b.size())
return 0;
else
for (int i=0; i < a.size() ; i++)
{
temp_book=a.getBook(i);
temp_title=temp_book.get_title();
if (!b.contains(temp_title))
return 0;
}
return 1;

}

void operator <<(ostream& outs, Library temp_library)
{
for (int i=0; i << temp_library.size(); i++)
{
outs << temp_library.getBook(i) ;
}
}

int main()
{

Library lib;
lib.readfile(filename);
lib.addBook(Book new_Book);
lib.contains(string test_title);
lib.size();
lib.getBook(int position);

Book b;
b.Book(string new_title, string new_publisher, int new_numpages)

char selection;
string filename;
cout<<"Welcome to Dave's woodworking library!"<<endl; //Intro
cout<<"Where everyone is getting hammered or nailed!"<<endl;
cout<<""<<endl;
cout<<"Please make your selction from the list below..."<<endl; //Asks user for input
cout<<"1. Read information about books from a file"<<endl;
cout<<"2. Find a book in the library"<<endl;
cout<<"3. Add your book to our library"<<endl;
cout<<"4. Print out the library's book collection"<<endl;
cout<<"5. Quit the program"<<endl; //Quits the program
cin>> selection;

switch(selection)
do{
case '1':
cout<< "Please enter your filename with the extension" <<endl;
cin>> filename;
void readfile(string filename);
Library lib;
lib.readfile(filename);


break;

case '2':
cout<< "Please enter the name of your book"<<endl;
cin>> title;
Library lib;
lib.contains(string test_title);
break;

case '3':
cout<<"Please enter the title, publisher and number of pages"<<endl;
cin>> title,publisher,numberofpages;
Library lib;
lib.addBook(Book new_Book);
break;

case '4':
//prints out the library's book collection
break;

case '5':
cout<<"Please don't leave us! The books come alive at night!"<<endl;
break;

default:
cout<<"That's not a possible choice...you must have wood for brains!"<<endl;
}while (selection !=4);

}

these are my errors:

:undefined identifer 'filename'
hello.cpp line 149 lib.readfile(filename);
: '(' expected
hello.cpp line 150 lib.addBook(Book new_Book);
: ';' expected
hello.cpp line151 lib.contains(string test_title);
: '(' expected
hello.cpp line 155 Book b;
:undefined identifier 'b'
hello.cpp line 156 b.Book(string new_title, string new_publisher,int new_numpages)
:',' expected
hello.cpp line 158 char selection;
:undefined identifier 'selection'
hello.cpp line 169 cin>>selection;
:undefined identifier 'selection'
hello.cpp line 171 switch(selection)
undefined identifier 'title'
hello.cpp line 185 cin>> title;
: '(' expected
hello.cpp line 186 lib.contains(string test_title);
: ';' expected
hello.cpp line 187 break;
:undefined identifier 'title'
hello.cpp line 191 cin>>title,publisher,numberofpages;
:'(' expected
hello.cpp line 192 lib.addbook(Book new_Book);
:';' expected
hello.cpp line 193 break;
:undefined identifier 'selection'
hello.cpp line 205 }while (selection !=4);

[Banfa]

As a general rule the switch statement should not be mixed up (interleaved) with other statements like you have done with your switch and while. Also a switch statement needs { and }

[code]
switch(expression)
{
case 1:
// case 1 code
break;

case 2:
// case 1 code
break;

// other cases

default:
// default code
break;
}

I suspect you switch should be inside you while not the other way round.


I is possible to construct switchs with intervealed other statements but these are hacks (normally speed hacks) and only for the advanced user in very special cases.