#include<iostream> #include<Cmath> using namespace std; class Point //定义坐标点类 { public: Point():x(0),y(0) {}; Point(double x0, double y0):x(x0),y(y0){}; void PrintPoint(); //输出点的信息 double getx() { return x; } double gety() { return y; } protected: double x,y; //点的横坐标和纵坐标 }; void Point::PrintPoint() { cout<<"Point: ("<<x<<","<<y<<")"; //输出点 } class Line: public Point //利用坐标点类定义直线类, 其基类的数据成员表示直线的中点 { public: Line(Point pts, Point pte); //构造函数,用初始化直线的两个端点及由基类数据成员描述的中点 double Length(); //计算并返回直线的长度 void PrintLine(); //输出直线的两个端点和直线长度 private: class Point pts,pte; //直线的两个端点,从Point类继承的数据成员表示直线的中点 }; double Line::Length() { return sqrt(pow((pts.getx()-pte.getx()),2)+pow((pts.gety()-pte.gety()),2)); } void Line::PrintLine() { cout<<"1st ("<<pts.getx()<<","<<pts.gety()<<")"<<endl; cout<<"2nd ("<<pte.getx()<<","<<pte.gety()<<")"<<endl; cout<<"长度:"<<Length()<<endl; } Line::Line(Point ps, Point pe):Point((ps.getx()+pe.getx())/2,(ps.gety()+pe.gety())/2) { pts=ps; pte=pe;//这一段不是太懂 } int main() { Point ps(-2,5),pe(7,9); Line l(ps,pe); cout<<"About the Line: "<<endl; l.PrintLine(); //输出直线l的信息:两端点及长度 cout<<"The middle point of Line is: "<<endl; l.PrintPoint(); //输出直线l中点的信息 return 0; }
时间: 2024-10-04 20:06:16