【原创】刚做完的C++练习题(作一个带选择的求矩形正方形和长方型面积程序)
作一个带选择的求矩形正方形和长方型面积程序
#include <iostream>
using namespace std;
class A{
protected:
int x;
int y;
public:
virtual void show() = 0;
};
class B:public A{
public:
void show(){
cout<<"输入矩形长和宽 :";
cin>>x>>y;
cout<<"矩行面积是 :"<<x*y<<endl;
}
};
class C:public A{
public:
void show(){
cout<<"输入三角形的低长和高 :";
cin>>x>>y;
cout<<"三角形面积是 :"<<(x*y)/2<<endl;
}
};
class D:public A{
void show(){
cout<<"输入正方形的边长 :";
cin>>x;
cout<<"正方形面积是 :"<<x*x<<endl;
}
};
void main()
{
char i='0';
A *p;
cout<<"1.矩行面积 "<<"2.三角形面积 "<<"3.正方形面积 "<<"4.退出"<<endl;
while(i!='4')
{
cout<<"选择 :";
cin>>i;
switch(i){
case '1':p = new B;p->show();break;
case '2':p = new C;p->show();break;
case '3':p = new D;p->show();break;
}
}
}
