Question

Write the definition of a member function push() for a class Library in C++ to insert a book information in a dynamically allocated stack of books considering the following code is already written as a part of the program:

struct book 

{ 

int bookid; 

char bookname[20]; 

book *next; 

}; 

class Library 

{ 

book *top; 

public: 

Library() 

{ 

top=NULL; 

} 

void push(); 

void pop(); 

void disp(); 

~Library(); 

};

Answer 1

void Library::push() 

{ 

book *nptr; 

nptr=new book; 

cout<<"Enter values for bookid and bookname";

cin>>nptr->bookid>>nptr->bookname;

nptr->next=NULL; 

if(top==NULL)

top=nptr; 

else 

{ 

nptr->next=top; 

top=nptr: 

}

}