zhihu question 26161075 code by lexdene

zhihu_26161075.cpp

#include <iostream>
using namespace std;

class Date
{
public:
    Date(int y=0, int m=0, int d=0):year(y), month(m), day(d){}
    friend bool operator>(const Date& da, const Date& db);
    int getyear()const;
    int getmonth()const;
    int getday()const;
private:
    int year;
    int month;
    int day;
};

int fake_number(const Date& da){
    return da.getyear() * 400 * 40 + da.getmonth() * 40 + da.getday();
}

bool operator>(const Date& da, const Date& db){
    return fake_number(da) > fake_number(db);
}

int Date::getyear()const{
    return year;
}

int Date::getmonth()const{
    return month;
}

int Date::getday()const{
    return day;
}

int main(){
    Date a(2014, 10, 22), b(2015, 1, 2);
    cout << (a > b) << endl;
    cout << (b > a) << endl;
    return 0;
}