How to relate user with a book (Library system) C++ - c++

Question

I am doing a university project and I am making a Library System.
It has a few restrictions I cannot use what we haven't been taught (so no vectors or std:: things).
Now, I have some classes made.
(1) Date
(2) Book
(3) Student
(4) Library //Haven't made it yet
Now, when a student/user issues a book their account number is being saved in "Book" class and so is the return_date.
Now, I wish to make a pointer or use this-> operator or something that will be in Student class but point to a Book class.
So, when Student wants to see which books they have currently issued will be displayed.
I am not sure how to do that.
Should I make a Library class, give it an array of "Book" class by composition and then make a member function in "Student/User" class and display it there?
I really want to use new/delete keyword, this, or pointers to do this. It's not compulsory but it will help me understand those concepts.
The following are my Book, Student and Date classes.
Date Class:
class Date
{
int Day; //1-31 based on month
int Month; //1-12
int Year; //any year
int checkDay(int );
int Late_Days;
public:
static const int Days_per_Month[13];
Date()
{
Day=0;
Month=0;
Year=0;
}
Date (int dy, int mn, int yr)
{
if (mn>0 && mn <=12)
Month=mn;
else
{
Month=1;
cout<<"Month "<<mn<<" invalid. Set to month 1"<<endl;
}
Year=yr;
Day=checkDay(dy);
}
void setDay(int d) {Day=d;}
void setMonth(int m) {Month=m;}
void setYear(int y) {Year=y;}
void setLateDay(int LD) {Late_Days=LD;}
int getDay() {return Day;}
int getMonth() {return Month;}
int getYear() {return Year;}
int getLateDay() {return Late_Days;}
void Print_Date()
{
cout<<getDay()<<"/"<<getMonth()<<"/"<<getYear()<<endl;
//cout<<Day<<"/"<<Month<<"/"<<Year<<endl;
}
void Update_Date()
{
cout<<"\nEnter Day: ";
cin>>Day;
cout<<"Enter Month: ";
cin>>Month;
cout<<"Year: ";
cin>>Year;
}
void increment_date(int num)
{
int day;
int month_new;
// Day=Day+num;
setDay(getDay()+num);
if( getDay()>Days_per_Month[getMonth()] )
{
day=getDay()-Days_per_Month[getMonth()];
setDay(day);
setMonth(getMonth()+1);
if(Days_per_Month[getMonth()]>12)
{
month_new=1;
setMonth(month_new);
setYear(getYear()+1);
}
}
Print_Date();
}
const int Date:: Days_per_Month[13]={0,31,28,31,30,31,30,31, 31, 30, 31, 30, 31};
int Date::checkDay(int testday) //returntype classname :: funcname (parameteres)
{
//static const int Days_per_Month[13]={0,31,28,31,30,31,30,31, 31, 30, 31, 30, 31};
if(testday > 0 && testday <= Days_per_Month[Month])
return testday;
if ( Month==2 && testday==29 && (Year%400==0 || (Year%4==0 && Year%100!=0)) ) //for leap year
return testday;
cout<<"Day "<<testday<<" invalid. Set to day 1."<<endl;
return 1;
}
Book Class
class Book
{
string Title;
string Author;
unsigned long int ISBN;
int Year_of_Publication;
int Library_Code;
string Category;
string Status;
unsigned int Account_Number; //if issued
int Copies_of_Book;
Date Return_Date;
public:
static int Copy_Number;
Book()
{
Title=" ";
Author=" ";
ISBN=0;
Year_of_Publication=0;
Library_Code=0;
Category=" ";
Status=" ";
Account_Number=0;
Copies_of_Book=0;
Return_Date.setDay(0);
Return_Date.setMonth(0);
Return_Date.setYear(0);
}
Book(string t, string a,unsigned long int isbn, int yop, int libcode, string c, string s, unsigned int an, int cob)
{
setTitle(t);
setAuthor(a);
setISBN(isbn);
setYOP(yop);
setLibraryCode(libcode);
setCategory(c);
setStatus(s);
setAccountNum(an);
setCopiesBook(cob);
}
void setTitle(string T) {Title=T;}
void setAuthor(string A) {Author=A;}
void setISBN(unsigned long int isbn){ISBN=isbn;}
void setYOP(int yop) {Year_of_Publication=yop;}
void setLibraryCode(int libcode) {Library_Code=libcode;}
void setCategory(string c) {Category=c;}
void setStatus(string s) {Status=s;}
void setAccountNum(unsigned int an) {Account_Number=an;}
void setCopiesBook(int cob) {Copies_of_Book=cob;}
void setCopyNumber(int cn) {Copy_Number=cn;}
string getTitle() {return Title;}
string getAuthor() {return Author;}
unsigned long int getISBN() {return ISBN;}
int getYOP() {return Year_of_Publication;}
int getLibraryCode() {return Library_Code;}
string getCategory() {return Category;}
string getStatus() {return Status;}
unsigned int getAccountNum() {return Account_Number;}
int getCopiesBook() {return Copies_of_Book;}
int getCopyNumber() {return Copy_Number;}
void Input_New_Book()
{
cout<<"\nEnter Title: ";
cin>>Title;
cout<<"Enter Author: ";
cin>>Author;
cout<<"Enter ISBN: ";
cin>>ISBN;
cout<<"Enter Year of Publication: ";
cin>>Year_of_Publication;
cout<<"Enter Library Code: ";
cin>>Library_Code;
cout<<"Enter Category: ";
cin>>Category;
cout<<"Enter Total Copies Number: ";
cin>>Copies_of_Book;
cout<<"Enter Status: ";
cin>>Status;
if(Status=="Issued")
{
cout<<"Enter Account Number: ";
cin>>Account_Number;
Return_Date.Update_Date();
}
}
void Display_Book_Info()
{
cout<<"\nTitle: "<<getTitle()<<endl;
cout<<"Author: "<<getAuthor()<<endl;
cout<<"ISBN: "<<getISBN()<<endl;
cout<<"Year of Publication: "<<getYOP()<<endl;
cout<<"Library Code: "<<getLibraryCode()<<endl;
cout<<"Category: "<<getCategory()<<endl;
cout<<"Total Copies: "<<getCopiesBook()<<endl;
cout<<"Status: "<<getStatus()<<endl;
if(getStatus()=="Issued")
{
cout<<"Account Number: "<<getAccountNum()<<endl;
cout<<"Return Date: ";
Return_Date.Print_Date();
}
}
void Update_Status()
{
unsigned int AN;
Display_Book_Info();
cout<<"Please enter the updated status of the book: ";
cin>>Status; //We cannot use string in an switch, so we are using if.
if (Status=="Lost")
{
cout<<"The book is lost."<<endl;
setAccountNum(0);
}
else if (Status=="Available")
{
cout<<"Book is available now to issue."<<endl;
setAccountNum(0); //This indicates it doesn't have nay account number.
}
else if(Status=="Issued")
{
cout<<"The book is in possession of someone."<<endl;
cout<<"Enter their account number:";
cin>>AN;
setAccountNum(AN);
}
else if (Status=="Order")
{
cout<<"The book is in process of being ordered."<<endl;
setAccountNum(0);
}
else
{
cout<<"Wrong entry!\nBook's Status is set to default. (Available)"<<endl;
Status="Available";
setAccountNum(0);
}
cout<<"Status updated successfully!"<<endl;
}
void Issue_Book(int day_num) //This day_num indicated number of days.
{
unsigned int an;
cout<<"Enter account number of User:";
cin>>an;
setAccountNum(an);
Return_Date.Update_Date();
cout<<"Book issued for "<<day_num<<" days."<<endl;
cout<<"Return Date: ";
Return_Date.Print_Date();
}
void ReIssue_Book(int day_num)
{
unsigned int an;
cout<<"Enter account number of User:";
cin>>an;
setAccountNum(an);
Return_Date.increment_date(day_num);
cout<<"Book issued for "<<day_num<<" more days."<<endl;
cout<<"Return Date: ";
Return_Date.Print_Date();
}
void Return_Book()
{
cout<<"Book returned from User: "<<getAccountNum()<<endl;
setAccountNum(0);
cout<<"Book returned successfully!"<<endl;
}
}; //end of class book
int Book::Copy_Number=0;
Student Class
class Student:public Book
{
string Name;
unsigned int Account_Number;
double Fine;
int Books_Issue;
public:
Student()
{
Name=" ";
Account_Number=0;
Fine=0;
Books_Issue=0;
}
void setName(string n) {Name=n;}
void setAccount_Number(unsigned int an) {Account_Number=an;}
void setFine(double f) {Fine=f;}
void setBooksIssue(int n) {Books_Issue=n;}
string getName() {return Name;}
unsigned int getAccount_Number() {return Account_Number;}
double getFine() {return Fine;}
int getBooksIssue() {return Books_Issue;}
void Input_Student_info()
{
cout<<"\nEnter Name: ";
cin>>Name;
cout<<"Enter Account Number: ";
cin>>Account_Number;
}
void Display_Student_info()
{
cout<<"Name: "<<getName()<<endl;
cout<<"Account Number: "<<getAccount_Number()<<endl;
cout<<"Total Fine: "<<getFine()<<endl;
cout<<"Books issued: "<<getBooksIssue()<<endl;
}
void Issue_a_book()
{
if(Books_Issue<=3)
{
Issue_Book(7); //This will issue a book and give it a 7 days return date time
Books_Issue++; //This will mean a book has been issued.
}
else
cout<<"Cannot issue book. You have reached your maximum limit.\nReturn a book in order to issue another."<<endl;
}
void Display_All_Books() //which are currently issued
{
for (int i=0 ; i<=getBooksIssue() ; i++)
{
}
}
};
Sorry for posting huge chunks of code. But some people say we should post the whole code, so this is why I posted all of it organized way.
The main question is:
How should I display issued books in a Student's class?
Should I make a Library class (as a parent class or child class, or use composition and arrays of Book class) first or at the very end?
Let me know what is the best way to do this.
Thank You so much.

Answer 1

It is better to have remove the user issue details from the book class...
Let the book class have only details about the book and methods to update and retrieve book details.
Add the user issue details into a new class which inherits the book class... This way is more modular and keeps the books as separate entities. Now you can make a linked list(as they are dynamic) or array of these classes, each holding a book and the issue and return dates for that particular student.
for example:
class books_issued{
public: book issued_book;
books_issued *new;
<put your issue data like:>
unsigned int Account_Number; //if issued
int Copies_of_Book;
Date Return_Date;
<and issue related methods:>
};
now declare an object of books_issued class in student class,
and write a method to add, remove and view books that have been issued by that particular student.
--- If you need any help with creating linked lists for this purpose, let me know I will be more than happy to help as I had done a very similar library management program for my project as well :-) ---