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; }
	friend bool operator <(string op1, Book op2) {
		if (op1 < op2.title)
			return true;
		else return false;
	}
};


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

	Book b1("청춘", 20000, 300);
	string b2;
	cout << "책 이름을 입력하세요>> ";
	getline(cin, b2);
	if (b2 < b1) cout << b1.getTitle() << "이 " << b2 << "보다 뒤에 있구나!" << endl;
}