클래스 Book ! 연산자 구현

#include <iostream>
#include <string>
using namespace std;

class Book {
	string title;
	int price, pages;
public:
	Book(string title = "", int price = 0, int pages = 0) {
		this->title = title;
		this->price = price;
		this->pages = pages;
	}
	void show() {
		cout << title << ' ' << price << "원 " << pages << "페이지" << endl;
	}
	string getTitle() { return title; }
	bool operator! ();
};

bool Book::operator!() {
	if (price == 0)
		return true;
	return false;
}


int main() {
	cout << "2018305065 전유정" << endl << endl;

	Book book("벼룩시장", 0, 50); 
	if (!book) cout << "공짜다" << endl;
}