C++问题 定义一个类，用于输入并验证日期

#include "iostream.h"
class date
{
public:
date();
date(date &d);
int setdate(int y, int m, int d);
inline int getyear(){return year;}
inline int getmonth(){return month;}
inline int getday(){return day;}
private:
int Reasonable(int y, int m, int d);
int year;
int month;
int day;
};

class qdate : public date
{
public:
int Query();
};

date::date()
{
year=1900; month=1; day=1;
}

date::date(date &d)
{
year=d.getyear(); month=d.getmonth(); day=d.getday();
}

int date::setdate(int y, int m, int d)
{
switch (Reasonable(y,m,d))
{
case 1:
printf("month is wrong! Retry, format yyyy-mm-dd:");
return 0;
case 2:
printf("day is wrong! Retry, format yyyy-mm-dd:");
return 0;
}
year=y; month=m; day=d;
ret