C++继承——两点间距离计算
C++:继承——两点间距离计算
给出下面的一个基类框架: class Point_1D { protected: float x;//1D 点的x坐标 public: Point_1D(float p = 0.0); float distance(const Point_1D & p2); } 以Point_1D为基类建立一个派生类Point_2D,增加一个保护数据成员: float y;//2D平面上点的y坐标 以Point_2D为直接基类再建立一个派生类Point_3D,增加一个保护数据成员: float z;//3D立体空间中点的z坐标 生成上述类并编写主函数,根据输入的点的基本信息,建立点对象,并能计算该点到原点的距离。 输入格式: 测试输入包含若干测试用例,每个测试用例占一行(点的类型(1表示1D点,2表示2D点,3表示3D点) 第一个点坐标信息(与点的类型相关) 第二个点坐标信息(与点的类型相关))。当读入0时输入结束,相应的结果不要输出。 输入样例: 1 -1 0 2 3 4 0 0 3 1 2 2 0 0 0 0 输出样例: Distance from Point -1 to Point 0 is 1 Distance from Point(3,4) to Point(0,0) is 5 Distance from Point(3,3,3) to Point(0,0,0) is 3
使用IDE为VS2017
#include "stdafx.h" #include <math.h> #include <iostream> using namespace std;
class Point_1D
{
protected:
float x;//1D 点的x坐标
public:
Point_1D(float p = 0.0) {
};
void set_1D()
{
cin >> x;
}
float distance(const Point_1D & p2)
{
float a;
a = fabs(x - p2.x);//求绝对值
cout << "Distance from Point " << x << " to Point " << p2.x
<< " is " << a << endl;
return a;
}
};
class Point_2D :public Point_1D
{
protected:
float y;
public:
void set_2D()
{
set_1D(); //调用基类的set函数
cin >> y;
}
float distance(const Point_2D & p2)
{
float a;
a = sqrt((x - p2.x)*(x - p2.x) + (y - p2.y)*(y - p2.y));
//开平方根,求到坐标原点的距离
cout << "Distance from Point(" << x << "," << y << ")
to Point(" << p2.x << "," << p2.y << ") is " << a << endl;
return a;
}
};
class Point_3D :public Point_2D
{
protected:
float z;
public:
void set_3D()
{
set_2D();
cin >> z;
}
float distance(const Point_3D & p2)
{
float a;
a = sqrt((x - p2.x)*(x - p2.x)
+ (y - p2.y)*(y - p2.y) + (z - p2.z)*(z - p2.z));
cout <<
"Distance from Point(" << x << "," << y << "," << z << ")
to Point(" << p2.x << "," << p2.y << "," << p2.z << ")is "
<< a << endl;
return a;
}
};
int main()
{
int type;
Point_1D a1, a2;
Point_2D b1, b2;
Point_3D c1, c2;
cin >> type;
while (type)
{
switch (type)
{
case 1:a1.set_1D();
a2.set_1D();
a1.distance(a2);
break;
case 2:b1.set_2D();
b2.set_2D();
b1.distance(b2);
break;
case 3:c1.set_3D();
c2.set_3D();
c1.distance(c2);
break;
}
cin >> type;
}
return 0;
}
