* 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: 第六周 任务四
* 作 者: 杨森
* 完成日期: 2012 年 4 月 1 日
* 版 本 号: V1.0
源程序:
#include<iostream>
#include<cmath>
using namespace std;
class CPoint
{
private:
double x; // 横座标
double y; // 纵座标
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 形式输入座标点
void output(); //以(x,y) 形式输出座标点
};
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
double a, b, c;
};
void CTriangle::setTriangle(CPoint &X, CPoint &Y, CPoint &Z)//
{
A = X;
B = Y;
C = Z;
}
double CTriangle::perimeter(void)//计算三角形的周长
{
a = B.Distance(C),b = C.Distance(A),c = A.Distance(B);
return (a+ b+ c);
}
double CTriangle::area(void)//计算并返回三角形的面积
{
a = B.Distance(C),b = C.Distance(A),c = A.Distance(B);
double q = (a+ b+ c)/2;
return sqrt(q* (q - a)* (q - b)* (q - c));
}
bool CTriangle::isRightTriangle() //是否为直角三角形
{
a = B.Distance(C),b = C.Distance(A),c = A.Distance(B);
if((a*a + b*b - c*c < 1e-7) || (a*a + c*c - b*b < 1e-7) || (b*b + c*c - a*a < 1e-7))
return true;
else
return false;
}
bool CTriangle::isIsoscelesTriangle() //是否为等腰三角形
{
a = B.Distance(C),b = C.Distance(A),c = A.Distance(B);
if((a - b < 1e-7) || (b - c < 1e-7) || (c - a < 1e-7))
return true;
else
return false;
}
CPoint::CPoint(double xx ,double yy )
{
x = xx;
y = yy;
}
double CPoint::Distance(CPoint p) const
{
double dis;
dis = sqrt((p.x - x) * (p.x - x) + (p.y - y) * (p.y - y));
return dis;
}
void CPoint::input()
{
char c;
cout << "以x,y形式输入座标" <<endl;
cin >> x >> c >> y;
while(1)
{
if( c != ',')
cout << "error!";
else
break;
}
}
void CPoint::output()
{
cout << "以(x,y)的形式输出座标点" <<endl;
cout << '(' << x << ',' << y << ')' <<endl;
}
void main()
{
CTriangle Tr1 (CPoint (0,3), CPoint (0,0), CPoint (4,0));
cout << "三角形的面积是:" << Tr1.area() << " " << endl <<"三角形的周长是:" << Tr1.perimeter() <<endl;
cout << "这个三角形" << (Tr1.isRightTriangle()? "是" : "不是" )<< "直角三角形" <<endl;
cout << "这个三角形" << (Tr1.isIsoscelesTriangle()? "不是" : "是") << "等腰三角形"<<endl;
}