这个错误不明白，请指教

程序代码如下：
#include<iostream.h>
#include<stdlib.h>
class Date{
      public:
             void setDate(int y,int m,int d);
             void showDate();
      private:
              int year;
              int month;
              int day;
      };
void Date::setDate(int y,int m,int d)
{
     year=y;
     month=m;
     day=d;
}
inline void Date::showDate()
{
       cout<<year<<"."<<month<<"."<<day<<endl;
}

int main()
{
     Date date1,date2,*date3;
     cout<<"Date1 set and output:"<<endl;
     date1.setDate(1998,4,28);
     date1.showDate();
     cout<<"Date2 set and output:"<<endl;
     date2.setDate(2002,11,14);
     date2.showDate();
     cout<<"Date3 set and output:"<<endl;
     date3->setDate(1998,10,25);
     date3->showDate();
     system("pause");
}
 程序命名为“类和对象”运行后出现下面这个对话框：


哪里出错了啊？请高手指教