抽象一个点，一个圆，并判断点与圆的关系。（在圆内还是圆外）

h文件进行类的声明；

cpp文件为类的实现细节；主要注重的细节为：

=================================================================================================================================

工程代码如下：

//MyCircle.h
#pragma once
#include"MyPoint.h"
class MyCircle
{
public:
	void setCir(double x, double y, double r);

public:
	char * judge(double x, double y);
	char * judge(MyPoint &p);

private:
	double x1, y1; //圆心坐标
	double r1;  //圆半径
};

//MyPoint.h
#pragma once
class MyPoint
{
private:
	double x0, y0; //点坐标
public:
	void setPoint(double x, double y);
	double getX0();
	double getY0();
};

//MyCircle.cpp
#include "MyCircle.h"

void MyCircle::setCir(double x, double y, double r)
{
	x1 = x; y1 = y; r1 = r;
}
char* MyCircle::judge(double x, double y)
{
	double s = (x1 - x)*(x1 - x) + (y1 - y)*(y1 - y) - r1*r1;
	if (s > 0)
	{
		return "在圆外";
	}
	else
	{
		return "在圆内";
	}
}
char* MyCircle::judge(MyPoint &p)
{
	double s = (x1 - p.getX0())*(x1 - p.getX0()) + (y1 - p.getY0())*(y1 - p.getY0()) - r1*r1;
	if (s > 0)
	{
		return "在圆外";
	}
	else
	{
		return "在圆内";
	}
}

//MyPoint.cpp
#include "MyPoint.h"

void MyPoint::setPoint(double x, double y)
{
	x0 = x;
	y0 = y;
}
double MyPoint::getX0()
{
	return x0;
}
double MyPoint::getY0()
{
	return y0;
}

//MainTestClass.cpp
#include "iostream"
#include "MyCircle.h"
#include "MyPoint.h"

using namespace std;

void main()
{
	MyCircle c1;
	MyPoint  p1;
	c1.setCir(2, 2, 3);
	p1.setPoint(1, 1);
	cout << c1.judge(p1.getX0(), p1.getY0()) << endl;
	cout << c1.judge(p1) << endl;

	system("pause");
}

【C/C++学院】（5）面向对象编程练习--h和cpp分开编写