01.cpp

主要完成试题的录入、查询、按比例随机组合试卷并打印出试卷等功能。 （2）使用Visual C++制作界面

  #include<iostream>
using namespace std;
// 声明抽象基类 shape
   template<typename T> 
class Shape 
{ 
public: 
virtual T Area() = 0;

}; 
    //一个shape基类模板派生出多个模板类
template<typename T> 
class Circle : public Shape<T> 
{ 
public: 
Circle(T radius) : radius_(radius); 
T Area(){ return T(3.14) * radius_*radius_; } 
private: 
T radius_; 
};

       
       template<class T>
          
       ostream &operartor<<(ostream &output,Circle<T> &c)
              { output<<"["<<c.x<<","<<c.y<<"],r="<<c.radius<<",area="<<c.area()<<endl;
              return output;}
        istream &operator>>(istream &input,Circle<T> &c)
              {
                cout<<"请输入圆的圆心和半径:";
               input>>"[">>c.x>>",">>c.y>>"],r=">>c.radius;
               return input;}

           float setcircle() const{cin>>[x,y]>>radius;}
       
     class dimetric:public circle<float> //正方形是circle类的公用派生类
     {public:
         dimetric(float r=0);
         float setdimetric() const{cin>>radius;}
          float area() const;    //计算正方形的面积 
           friend ostream &operator<<(ostream &,const demetric &); //重载运算符"<<"
            friend istream &operator>>(istream &,const demetric &); //重载运算符">>"
        }
          
         //定义dimetric类成员函数
      dimetric::dimetric(float r):radius(r)()

      //重载运算符">>","<<"
       float dimetric::area() const{return radius*radius;)
         ostream &operator<<(ostream &output,const demetric &cz)
       {output<<"radius="<<cz.radius<<","<<"area="<<cz.area()<<endl;
          return output;}
          istream &operator>>(istream &input,const demetric &cz)
       { cout<<"请输入正方形的边长:";
           input>>"r=">>cz.radius;
           return input;}
        
        //定义主函数
       int main()
     {cout<<"---------------------计算圆和正方形的面积----------------"
       circle<float>c1;
         cin>>c1;
         cout<<c1;
       demetric c2;
         cin>>c2;
         cout<<c2;
       return 0;
     }