项目四

#include<iostream>
#include<cmath>
using namespace std;

//类1
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
  void input();  //以x,y 形式输入坐标点
  void output(); //以(x,y) 形式输出坐标点
};


//类2
class CTriangle
{
public:
	CTriangle(CPoint &X,CPoint &Y,CPoint &Z):A(X),B(Y),C(Z){} //给出三点的构造函数
	void setTriangle(CPoint &X,CPoint &Y,CPoint &Z);//
	float perimeter(void);//计算三角形的周长
	float area(void);//计算并返回三角形的面积
	bool isRightTriangle(); //是否为直角三角形
	bool isIsoscelesTriangle(); //是否为等腰三角形
private:
	CPoint A,B,C; //三顶点
};

CPoint::CPoint(double xx,double yy)
{

   x=xx;
   y=yy;
}


double CPoint::Distance(CPoint p) const
{
   return (sqrt((x-p.x)*(x-p.x)+(y-p.y)*(y-p.y)));
}

void CPoint::input()
{ 
	char ch;
  cout<<"请输入(x,y)的值";
  cin>>x>>ch>>y;
  if(ch!=',')
   cout<<"您输入的形式不对：";
//   break;
}

void CPoint::output()
{
  cout<<"("<<x<<","<<y<<")";

}

void CTriangle::setTriangle(CPoint &X,CPoint &Y,CPoint &Z)
{
   A=X;
   B=Y;
   C=Z;

}

float CTriangle::perimeter(void)//周长
{   
	double a=A.Distance(B),b=B.Distance(C),c=A.Distance(C);
	return (a+b+c);
  
}

float CTriangle::area(void)//面积
{
	double a=A.Distance(B),b=B.Distance(C),c=A.Distance(C);
    double s;
    s=0.5*(a+b+c);
	return (sqrt(s*(s-a)*(s-b)*(s-c)));
}

bool CTriangle::isRightTriangle()
{
    double a=A.Distance(B),b=B.Distance(C),c=A.Distance(C);
    if(a*a==b*b+c*c&&b*b==a*a+c*c&&c*c==a*a+b*b)
		return true;
	else 
		return false;
}

bool CTriangle::isIsoscelesTriangle()
{
   double a=A.Distance(B),b=B.Distance(C),c=A.Distance(C);
   if(a==b&&a==c&&c==b)
	   return true;
   else
	   return false;
}

int main()
{
 CPoint a,b,c,*p1,*p2,*p3;
 p1=&a;
 p2=&b;
 p3=&c;
 CTriangle t1(*p1,*p2,*p3);
 cout<<"第一个点a："<<endl;
 a.input();
 cout<<"第二个点b："<<endl;
 b.input();
 cout<<"第三个点c"<<endl;
 c.input();


 cout<<"三角形的周长为："<<t1.perimeter()<<endl;
 cout<<"三角形的面积为："<<t1.area()<<endl;
 cout<<"该三角形"<<(t1.isRightTriangle()?"是":"不是")<<"直角三角形"<<endl;
 cout<<"该三角形"<<(t1.isIsoscelesTriangle()?"是":"不是")<<"等腰三角形"<<endl;
return 0;
}