2012年 上半年 第六周 C++程序设计 （十七）

【任务3】设计平面坐标点类，计算两点之间距离、到原点距离、关于坐标轴和原点的对称点等
enum SymmetricStyle { axisx,axisy,point};//分别表示按x轴, y轴, 原点对称
class CPoint
{
private:
double x;  // 横坐标
double y;  // 纵坐标
public:
CPoint(double xx=0,double yy=0);
double Distance(CPoint p) const;   // 两点之间的距离(一点是当前点，另一点为参数p)
double Distance0() const;          // 到原点的距离
CPoint SymmetricAxis(SymmetricStyle style) const;   // 返回对称点
void input();  //以x,y 形式输入坐标点
void output(); //以(x,y) 形式输出坐标点
};

#include<iostream>

#include<cmath>

using namespace std;

enum SymmetricStyle { axisx,axisy,point};//分别表示按x轴, y轴, 原点对称
class CPoint
{
private:
mutable double x;  // 横坐标
mutable double y;  // 纵坐标
public:
CPoint(double xx=0,double yy=0);
double Distance(CPoint p) const;   // 两点之间的距离(一点是当前点，另一点为参数p)
double Distance0() const;          // 到原点的距离
CPoint SymmetricAxis(SymmetricStyle style) const;   // 返回对称点
void input();  //以x,y 形式输入坐标点
void output(); //以(x,y) 形式输出坐标点
};
int main()
{
CPoint c1,c2;
c1.input();
cout<<c1.Distance0()<<endl;
c2.input();
cout<<c1.Distance(c2)<<endl;
c1.SymmetricAxis(axisx);
cout<<endl;
return 0;
}

CPoint::CPoint(double xx,double yy)
{
x=xx;
y=yy;
}
void CPoint::input()
{
bool found;
found=true;
cout<<"请您输入一个点的横纵坐标：（以“x,y”的形式输入）";
char m;
while(found)
{
cin>>x>>m>>y;
if(m!=',')
{
cout<<"您输入的格式不正确，请从新输入。";
}
else
{
found=false;
}
}
}
void CPoint::output() //以(x,y) 形式输出坐标点
{
cout<<"("<<x<<","<<y<<")"<<endl;
}
double CPoint::Distance0() const
{
double d;
d=sqrt(x*x+y*y);
cout<<"点("<<x<<","<<y<<")"<<"到原点的距离为:";
return d;
}

double CPoint::Distance(CPoint p) const
{
double d;
d=sqrt((p.x-x)*(p.x-x)+(p.y-y)*(p.y-y));
cout<<"点p("<<p.x<<","<<p.y<<")"<<"与点q("<<x<<","<<y<<")的距离为:";
return d;
}
CPoint CPoint::SymmetricAxis(SymmetricStyle style)  const  // 返回对称点
{
switch(style)
{
case axisx:
cout<<"点("<<x<<","<<y<<")"<<"关于x轴对称的点为：";
x=-x;
cout<<"("<<x<<","<<y<<")";
break;
case axisy:
cout<<"点("<<x<<","<<y<<")"<<"关于y轴对称的点为：";
y=-y;
cout<<"("<<x<<","<<y<<")";
break;
case point:
cout<<"点("<<x<<","<<y<<")"<<"关于原点对称的点为：";
x=-x;
y=-y;
cout<<"("<<x<<","<<y<<")";
break;
}
return 0;
}