对C++下struct 和 类默认继承的认识

 #include <iostream>
 using namespace std;
 struct  struct1{
     int data1 ;
     double data2 ;
     struct1(){
         (*this).data1 = data1 ;
         (*this).data2 = data2 ;
         cout<<"this is output by struct1 function !";
     }
     public :
     void privateFunc(){
         cout<<"this is private function , so this massage should never show in console ! \n";
     }
 };
 struct struct2 : struct1{
     /*

     according the result in console , we can get the conclusion :

     the default inherit method of struct is public 

     */
 };
 class class1 : public  struct1 {
     /*

     if ignore 'public' identifiers , compile will show that privateFunc() in 35 line 

     can't access, this indicate that it is private inhert when subclass is a struct. 

     */
     string name ;
     public :
     class1(){
         name = "i'm a class !";
         cout<<"this is output by class1 !";
     }
 };
 class class2{
     public :
     void showClass2(){
         cout<<"this is output by class2 ! \n ";
     }
 };
 class class3 : class2{
     /*

     according to the result : showClass2 can't accessiable can prove class default 

     inherit method is private 

     */
 };
 struct struct4 : class2{
     /*

     default inherit is public 

     */
 };
 class class4 : struct1 {
     /*

     default inherit is private
     */
 }
 int main(){
     //struct2 onestruct2 ;
     //onestruct2.privateFunc();
     /* test class default inherit */
     //class3 * oneclass3 = class3;
     //oneclass3->showClass2();
     /* test struct inherit class */
     //struct4 onestruct4 ;
     //onestruct4.showClass2();
     class4 * oneclass4;
     oneclass4->privateFunc();
     return ;
 }