单选题 有如下程序：
#include＜iostream＞
using namespace std;
class B{
public:
B(int xx):x(xx){++count;x+=10;}
virtual void show()const
{cout＜＜count＜＜"_"＜＜x＜＜endl;}
protected:
static int count;
private:
int x;
};
class D:public B{
public:
D(int xx,int yy):B(xx),y(yy)(++count;y+=100;}
virtual void show()const
{cout＜＜count＜＜"_"＜＜y＜＜endl;}
private:
int y;
};
int B::count=0;
int main(){
B*ptr=new D(10,20);
ptr-＞show();
delete ptr;
return 0;
}
运行时的输出结果是______。