c++ 类的学习2

#include<iostream>
#include<stdlib.h>
#include<string>
using namespace std;
class Time
{
  public:
     void set_time(); //公有成员函数，声明函数 
     void show_time();//公有成员函数，声明函数 
     private:
        int hour;
        int minute;
        int sec;
};
int main( )
{
    Time t1,t2;
    t1.set_time(); 
    t1.show_time();
    t2.set_time();
    t2.show_time();
    system("pause");
    return 0;
}
void Time::set_time( )
{
    cin>>hour>>minute>>sec;
}
void Time::show_time()
{
    cout<<hour<<":"<<minute<<":"<<sec<<endl;
}

#include<iostream>
#include<string>
#include<stdlib.h>
using namespace std;
class student
{
 public: 
    void display()
    {
     cout<<"num:"<<num<<endl;
     cout<<"name:"<<name<<endl;
     cout<<"sex:"<<sex<<endl;
    }
    void set( )
    {
     cin>>num;
     cin>>name;
     getchar();
     cin>>sex;
    }
    private:
        int num;
        char name[20];
        char sex;
}stud1,stud2;
int main() 
{
  stud1.set();
  stud1.display();
  system("pause");
  return 0;
}