C++多重继承二义性原理实例解析

#include <iostream>
using namespace std;
 
class A{
public:
  int a;
};
 
class B1 : public A{
public:
  int b1;
};
 
class B2 : public A{
public:
  int b2;
};
 
class C : public B1, public B2{
public:
  int c;
};
int main(){
  C c1;
  c1.b1 = 100;
  c1.b2 = 200;
  c1.c = 300;
 
  c1.a = 500; //报错，不能确定成员变量a具体在那个类
 
  cout << "end..." << endl;
  system("pause");
  return 0;
}

#include <iostream>
using namespace std;
 
class A{
public:
  int a;
};
 
class B1 : virtual public A{
public:
  int b1;
};
 
class B2 : virtual public A{
public:
  int b2;
};
 
class C : public B1, public B2{
public:
  int c1;
};
 
int main(){
  C c1;
  c1.b1 = 100;
  c1.b2 = 200;
  c1.c1 = 300;
 
  c1.a = 500; //虚继承使得成员变量a只有一份拷贝，通过虚指针可以确定地址
 
  cout << "end..." << endl;
  system("pause");
  return 0;
}

#include<iostream>
using namespace std;
 
 
class Base1 {
public:
  void fun() {
    cout << "I am base-1 " << endl;
  };
};
 
class Base2
{
public:
  void fun() {
    cout << "I am base-2 " << endl;
  };
};
 
class A: public Base1, public Base2 {
public:
  void print() {
  }
};
 
int main() {
  A obj;
  obj.fun();  //调用的方法产生歧义
  system("pause");
  return 0;
}