P258 11.3  # include<iostream.h>   class Date  {   int year;  int month;  int day; public:   Date(); Date(int year,int month,int day); void addOneDay(Date &date); void setDate(Date &date); void displayDate(Date &date); int isLeapYear(int year);}; Date::Date() { } Date::Date(int year,int month,int day) {  this->year=year; this->month=month; this->day=day;} void Date::addOneDay(Date &date)   {    switch(date.month)   {   case 1://31天的月份   case 3:   case 5:   case 7:   case 8:   case 10:    if(date.day==31)   {    date.month+=1;   date.day=1;  }   else    date.day+=1;  break;  case 12://31天的12月可能进入到下一年    if(date.day==31)   {    date.year+=1;   date.month=1;   date.day=1;  }   else    date.day+=1;  break;  case 4://30天的月份   case 6:   case 9:   case 11:    if(date.day==30)    {     date.month+=1;    date.day=1;   }    else     date.day+=1;   break;   case 2://2月有闰年与平年之分     if(isLeapYear(date.year))    {     if(date.day==29)    {     date.month+=1;    date.day=1;   }    else     date.day+=1;   }    else    {     if(date.day==28)    {     date.month+=1;    date.day=1;   }    else     date.day+=1;  }    break;    }} int Date::isLeapYear(int year) {  //能被4和100整除,但不能被400整除. return (year%4==0&&year%100==0)||(year%400==0);}  void Date::setDate(Date &date)//注意参数传递 {  int year; int month; int day; cout<<"Please input year:"; cin>>year; cout<<"Please input month:"; cin>>month;  while(month>12)  {   cout<<"Please input month less than 12:";  cin>>month; }  cout<<"Please input day:";  cin>>day;  while(day>31)  {   cout<<"Please input day less than 31:";  cin>>month; }  date.year=year;  date.month=month;  date.day=day; }   void Date::displayDate(Date &date)  {   cout<<date.day<<"/"   <<date.month<<"/"  <<date.year<<endl;}    void main()    {     Date date1(2000,2,28);    date1.addOneDay(date1);    Date date2;    date2.setDate(date2);    date2.displayDate(date2);   }

评论