(1)
#include
using namespace std;
class CommonBase
{
int co;
//virtual void fun(){ }
};
class Base1 : virtual public CommonBase
{
public:
virtual void print1() { }
virtual void print2() { }
private:
int b1;
};
class Base2 : virtual public CommonBase
{
public:
virtual void dump1() { }
virtual void dump2() { }
private:
int b2;
};
class Derived : public Base1, public Base2
{
public:
void print2() { }
void dump2() { }
// virtual void hello(){ }
private:
int d;
};
int main()
{
cout << sizeof(Derived) << endl; //输出32
system("pause");
}
(2)
#include
using namespace std;
class CommonBase
{
int co;
virtual void fun(){ }
};
class Base1 : virtual public CommonBase
{
public:
virtual void print1() { }
virtual void print2() { }
private:
int b1;
};
class Base2 : virtual public CommonBase
{
public:
virtual void dump1() { }
virtual void dump2() { }
private:
int b2;
};
class Derived : public Base1, public Base2
{
public:
void print2() { }
void dump2() { }
//virtual void hello(){ }
private:
int d;
};
int main()
{
cout << sizeof(Derived) << endl; //输出36
system("pause");
}
(3)
#include
using namespace std;
class CommonBase
{
int co;
// virtual void fun(){ }
};
class Base1 : virtual public CommonBase
{
public:
virtual void print1() { }
virtual void print2() { }
private:
int b1;
};
class Base2 : virtual public CommonBase
{
public:
virtual void dump1() { }
virtual void dump2() { }
private:
int b2;
};
class Derived : public Base1, public Base2
{
public:
void print2() { }
void dump2() { }
virtual void hello(){ }
private:
int d;
};
int main()
{
cout << sizeof(Derived) << endl; //输出32
system("pause");
}
为什么(3)在32位系统上输出的是32而不是36?