有如下程序,没有使用多态机制。#include<iostream>using namespace std;class Base{ int a,b;public: Base(int x,int y){a=x;b=y;} void show(){cout<<a<<','<<b<<endl;}};class Derived:public Base{ int c,d;public: Derived(int x,int y,int z,int m):Base(x,y){c=z;d=w;} void show(){cout<<c<<','<<d<<endl;}};int main(){ Base B1(50,50),*pb; Derived D1(10,20,30,40); pb=&D1; pb->show(); return 0;}运行时输出的结果是
A.10,20
B.30,40
C.20,30
D.50,50