??????c++???锌????校???????????????????????public??protected??private????????????????????????????????????????????????????struct????????????public??校?class????????????private??小????Java?泻???????Java??????public??校???????泄??屑?小?
????1.???public???????????????????????????public??protected????????????????????????????????????public?????
??????1???????public??????????????????public???
??????2???????械?protected??????????????????protected???
??????3???????械?private????????????胁???????
????2.???protected???????????????????????????public??protected?????????????????????????????????????????????????????????????谐??????????????????械?public??protected???????
??????1???????public????????????斜??protected?????
??????2???????protected??????????????????protected?????
??????3???????械?private????????????胁???????
????3.???private???????????????????????????public??protected?????????????????????????????????????????????????????????????谐??????????????????械?public??protected???????
??????1???????public????????????斜??private?????
??????2???????protected????????????斜??private?????
??????3???????private????????????胁???????
???????????????????????????????????????????????
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??????????????????
????#include <iostream> 
????class Base { 
????public: 
????int public_a; 
????virtual void test() = 0; 
????protected: 
????int protected_a; 
????private: 
????int private_a; 
????}; 
????//???屑?? 
????class PublicDerived : public Base { 
????public: 
????virtual void test() { 
????public_a = 1;                   //public_a public??泻???public???? 
????protected_a = 2;                //protected_a ????protected???? 
????//private_a = 3;                  //????????????????谐?? 
????} 
????}; 
????//??????? 
????class ProtectedDerived : protected Base { 
????public: 
????virtual void test() { 
????public_a = 1;                   //public_a protected??泻???protected???? 
????protected_a = 2;                //protected_a ????protected???? 
????//private_a = 3;                //????????????????谐?? 
????} 
????}; 
????//??屑?? 
????class PrivateDerived : private Base { 
????public: 
????virtual void test() { 
????public_a = 1;                   //public_a private??泻???private???? 
????protected_a = 2;                //protected_a private??泻???private???? 
????//private_a = 3;                //????????????????谐?? 
????} 
????}; 
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