填空题

有以下程序 #include <iostream> using namespace std; class Base { int a; public: Base(int x) { a=x; } void show() { cout<<a; } class Derived: public Base { int b; public: Defived(int i):Base(i+ 1 ),b(i) {} void show() { cout<<b; } }; int main() { Base b(5),*pb; Derived d(1); pb=&d; pb->show(); return 0; } 运行后的打印结果是 【13】

【参考答案】

B