#include <iostream>
using namespace std;
class BASE
{
private:
    char c;
public:
    BASE(char n):c(n) {}
    virtual ~BASE()
    {
        cout<<c;
    }
};

class DERIVED:public BASE
{
private:
    char c;
public:
    DERIVED(char n):BASE(n+1),c(n) {}
    ~DERIVED()
    {
        cout<<c;
    }
};
int main()
{
    DERIVED d('X');
    return 0;
}
 

心得：基類中是虛擬函式，所以呼叫派生類裡面的再呼叫基類裡面的！派生類裡面得c是x基類裡面的是x+1=y所以。。。