C++ Input and Output

Compiled in Visual Studio 2017.

#include "stdafx.h"
#include<stdio.h>
#include<cstdio>
#include<iostream>

#define size 50

using namespace std;

class card {

    char title[size];
    char author[size];
    int num_book;

public:
    void store();
    void show();
};

void card::store()
{
    cout << "Enter Title: "; std::cin.getline(title,size); //cin >> title;

    cout << "Enter Author: "; std::cin.getline(author,size); //cin >> author;

    cout << "Enter number of copies: "; cin >> num_book;
	getchar();
	// if char std::cin.getline(num_book, 3);

}

void card::show()
{

	std::cout << "\nTitle: " << title << "  \nAuthor: " << author << "\nCopies: " << num_book;

}

// ENTRY POINT - GOVERNOR
int main()
{
    int choice;

    card b1, b2;

    cout << "{{{ Library Management System }}}\n\n";

// INPUT
    cout << "\nStore book-1 information\n";
    b1.store();

    cout << "\nStore book-2 information\n";
    b2.store();

// OUTPUT
    cout << "\n\nInformation of book-1";
    b1.show(); 

    cout << "\n\nInformation of book-2";
    b2.show();
    cin.get();

}

Screenshot