阅读程序2

#include <iostream>using namespace std;class BASE{private:    char c;public:    BASE(char n):c(n){}    virtual ~BASE(){cout<<c;}};class DERIVED:public BASE{    char c;public:    DERIVED(char n):BASE(n+1),c(n){}    ~DERIVED(){cout<<c;}};int main(){   DERIVED d('x');    return 0;}