学步园

/* (程序头部注释开始)  
* 程序的版权和版本声明部分  
* Copyright (c) 2011, 烟台大学计算机学院学生   
* All rights reserved.  
* 文件名称：三角形坐标类                              
* 作    者：张旭                                
* 完成日期：  2012   年   3   月    19  日  
* 版 本 号：略             
* 对任务及求解方法的描述部分  
* 输入描述：略   
* 问题描述：略   
* 程序输出：略   
* 程序头部的注释结束  
*/

#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:

	double x;  // 横坐标

	double y;  // 纵坐标

public:

	CPoint(double xx=0,double yy=0):x(xx), y(yy){}

	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
};

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);

	double perimeter (void);//计算三角形的周长

	double 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
};

int main ()
{
	CTriangle q (CPoint(3,0),CPoint(0,0),CPoint(0,4));

	cout<<"该三角形的周长为："<<q.perimeter()<<"，面积为："<<q.area()<< endl;

	cout<<"该三角形"<<(q.isRightTriangle()?"是":"不是")<<"直角三角形"<<endl;

	cout<<"该三角形"<<(q.isIsoscelesTriangle()?"是":"不是")<<"等腰三角形"<<endl;

	system ("pause");

	return 0;
}

void CPoint::input()
{
	cout << "请输入横坐标和纵坐标（x，y）：" << endl;

	double a = 0, b = 0;

	char q;

	while (250)
	{
		cin >> a >> q >> b;

		if (a != 0 && b != 0 && q == ',')
		{
			break;
		}
		cout << "error! try again." << endl;
	}

	x = a;

	y = b;
}

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

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

double CPoint::Distance0() const
{
	return sqrt(x * x + y * y);
}

CPoint CPoint::SymmetricAxis(SymmetricStyle style) const
{
	switch (style)
	{
	case 0:cout << '(' << x << ',' << -y << ')';break;

	case 1:cout << '(' << -x << ',' << y << ')';break;

	case 2:cout << '(' << -x << ',' << -y << ')';break;

	default:cout << "error!" << endl;
	}
	return 0;
}

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

	B = Y;

	C = Z;
}

double CTriangle::perimeter ()
{
	return A.Distance (B) + B.Distance (C) + C.Distance (A);
}

double CTriangle::area()
{
	double p = perimeter () / 2;

	return sqrt (p * (p - A.Distance (B)) * (p - B.Distance (C)) * (p - C.Distance (A)));
}

bool CTriangle::isIsoscelesTriangle () 
{
	if (A.Distance (B) == B.Distance (C) ||
		B.Distance (C) == C.Distance (A) ||
		A.Distance (B) == C.Distance (A))

		return true;

	else 

		return false;
}

bool CTriangle::isRightTriangle ()
{
	if (A.Distance (B) * A.Distance (B) + B.Distance (C) * B.Distance (C) == C.Distance (A) * C.Distance (A) ||
		C.Distance (A) * C.Distance (A) + A.Distance (B) * A.Distance (B) == B.Distance (C) * B.Distance (C) ||
		B.Distance (C) * B.Distance (C) + C.Distance (A) * C.Distance (A) == A.Distance (B) * A.Distance (B))

		return true;

	else

		return false;
}