有如下程序:#includeusing name space std;classB{public:B(int xx):x(xx){++count;x+=10;}virtu
有如下程序: #include using name space std; classB{ public: B(int xx):x(xx){++count;x+=10;} virtual void show()const {cout<<count<<'_'<<x<<endl;} protected: static int count; private: intx; }; class D:publicB{ public: D(int xx,int yy):B(xx),y(yy){++count;y+=100;} virtual void show()const {cout<<count<<'_'<<y<endl}; pnvate: inty; }; int B::count=0; intmain(){ B*ptr=new D(10,20); ptr->show(); delete ptr; return 0; } 运行时的输出结果是()。
A.1_120
B.2_120
C.1_20
D.2_20