제1 2 주 임무 2 (기본 구성원 의 방문 한정 부적 과 파생 류 의 계승 방식 이해)

/* (        ) 
*              
* Copyright (c) 2011,             
* All rights reserved. 
*     ：    
*    ： 
*     ： 2012   5   7   
*      ： 

*               
*     ： 
*     ：                  ，                  
*     ： 
*           
#include<iostream>
#include<string>
using namespace std;
class Student //（1）  student                  ，        
{public: 
	Student(int n,string nam,char s) ;
	void show();
	~Student( ){ } 
 protected: //   private   Student::sex”:      private   
	int num;
	string name;
	char sex ; 
};

class Student1: public Student //  protected “Student::show”    ，  “Student1”  “protected” “Student”  
{ public: 
Student1(int n,string nam,char s,int a,string ad);
	void show1( );
	~Student1( ){ } 
 private: 
	int age; 
	string addr; 
};

Student::Student(int n,string nam,char s) 
{	num=n;
	name=nam;
	sex=s; 
}
void Student::show()
{	cout<<"num: "<<num<<endl;
	cout<<"name: "<<name<<endl;
	cout<<"sex: "<<sex<<endl<<endl;
}

Student1:: Student1(int n,string nam,char s,int a,string ad):Student(n,nam,s) 
{     age=a; 
	  addr=ad;
}
void Student1::show1( )
{	cout<<"num: "<<num<<endl;
	cout<<"name: "<<name<<endl;
	cout<<"sex: "<<sex<<endl;
	cout<<"age: "<<age<<endl;
	cout<<"address: "<<addr<<endl<<endl;
}

int main( )
{	Student1 stud1(10010,"Wang-li",'f',19,"115 Beijing Road,Shanghai");
	Student1 stud2(10011,"Zhang-fun",'m',21,"213 Shanghai Road,Beijing");
	Student stud3(20010,"He-xin",'m');
	stud1.show1( ); 
	stud2.show( ); 
	stud3.show( ); 
	system("pause");
	return 0;
}
  ：   ： 
 Student          ，         ：error C2248: “Student::num”:      private   ( “Student”    ) 
                        ，       ，        
   ： 
       protected，         ： error C2247: “Student::show”    ，  “Student1”  “protected” “Student”   
                      
   ： 
       private，         ： error C2247: “Student::show”    ，  “Student1”  “private” “Student”   
                    ，          ！ 
  ：1.                     ，        
2.                      ，       
3.       ，              ， 
    ，        ，         
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