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设计一个圆形类(AdvCircle)和一个点类(Point)，计算点和圆的关系。

#include
   
    using namespace std;#include
    
     class AdvCircle {
   public:	AdvCircle(int x0,int y0,int r):m_x0(x0),m_y0(y0),m_r(r){
   }	int getX0() const{
   		return m_x0;	}	int getY0() const {
   		return m_y0;	}	int getR() const {
   		return m_r;	}private:	int m_x0;	int m_y0;	int m_r;};class Point {
   public:	Point(int x1,int y1):m_x1(x1),m_y1(y1){
   }	int getX1() const {
   		return m_x1;	}	int getY1() const {
   		return m_y1;	}private:	int m_x1;	int m_y1;};void judge(const AdvCircle& c, const Point& p) {
   	double ret = pow((p.getX1() - c.getX0()), 2) + pow((p.getY1() - c.getY0()), 2);	if (ret == c.getR()*c.getR()) {
   		cout << "点在圆上" << endl;	}	else if (ret > c.getR()*c.getR()) {
   		cout << "点在圆外" << endl;	}	else {
   		cout << "点在圆内" << endl;	}}void test01() {
   	AdvCircle c1(0, 0, 10);	Point p1(3, 4);	judge(c1, p1);}int main1() {
   	test01();	system("pause");	return 0;}
    
   

写法2：将圆心坐标作为点类，作为圆类的一个成员属性(全局函数方法)

#include
   
    using namespace std;#include
    
     #if(1)class Point {
   public:	//Point(int x, int y) :m_x(x), m_y(y) {}	//Error	C2280	'AdvCircle::AdvCircle(void)': attempting to reference a deleted function		//错误c2280 'AdvCircle::AdvCircle(void)':试图引用一个已删除的函数	//使用构造函数初始化Point类对象时出现上述错误#if(1)	void setXY(int x, int y) {
   		m_x = x;		m_y = y;	}#endif	int getX() {
   		return m_x;	}	int getY() {
   		return m_y;	}private:	int m_x;	int m_y;};#endifclass AdvCircle {
   public:	void setR(int r) {
   		m_r = r;	}	int getR() {
   		return m_r;	}	//设置圆心	void setCenter(Point &p) {
   		m_center = p;	}	//获取圆心	Point getCenter() {
   		return m_center;	}	private:	Point m_center;	int m_r;};//利用全局函数判断点和圆的关系void isInCircle(AdvCircle &c, Point &p) {
   	double ret = pow((p.getX() - c.getCenter().getX()), 2) + pow((p.getY() - c.getCenter().getY()), 2);	if (ret == c.getR()*c.getR()) {
   		cout << "点在圆上" << endl;	}	else if (ret > c.getR()*c.getR()) {
   		cout << "点在圆外" << endl;	}	else {
   		cout << "点在圆内" << endl;	}}void test01() {
   	Point p1;	p1.setXY(3, 4);	Point center;	AdvCircle c1;	center.setXY(0, 0);	c1.setR(1);	c1.setCenter(center);	isInCircle(c1, p1);}int main() {
   	test01();	system("pause");	return 0;}
    
   

成员函数方法：

#include
   
    using namespace std;#include
    
     class Point {
   public:	//Point(int x, int y) :m_x(x), m_y(y) {}	//Error	C2280	'AdvCircle::AdvCircle(void)': attempting to reference a deleted function		//错误c2280 'AdvCircle::AdvCircle(void)':试图引用一个已删除的函数	//使用构造函数初始化Point类对象时出现上述错误	void setXY(int x, int y) {
   		m_x = x;		m_y = y;	}		int getX() {
   		return m_x;	}	int getY() {
   		return m_y;	}private:	int m_x;	int m_y;};class AdvCircle {
   public:	void setR(int r) {
   		m_r = r;	}	//设置圆心	void setCenter(Point &p) {
   		m_center = p;	}	//获取圆心	Point getCenter() {
   		return m_center;	}	//利用成员函数判断点和圆的关系	void isInCircle(Point p) {
   		double ret = pow((p.getX() - m_center.getX()), 2) + pow((p.getY() - m_center.getY()), 2);		if (ret == m_r*m_r) {
   			cout << "点在圆上" << endl;		}		else if (ret > m_r*m_r) {
   			cout << "点在圆外" << endl;		}		else {
   			cout << "点在圆内" << endl;		}	}	private:	Point m_center;	int m_r;};void test02() {
   	AdvCircle a;	Point p;	p.setXY(3, 4);	a.setR(51);	Point center;	center.setXY(0, 0);	a.setCenter(center);	int r = a.getR();	a.isInCircle(p);}int main() {
   	test02();	system("pause");	return 0;}
    
   

分文件编写

main.cpp#include
   
    using namespace std;#include
    
     #include"circle.h"#include"point.h"//利用全局函数判断点和圆的关系void isInCircle(AdvCircle &c, Point &p) {
   	double ret = pow((p.getX() - c.getCenter().getX()), 2) + pow((p.getY() - c.getCenter().getY()), 2);	if (ret == c.getR()*c.getR()) {
   		cout << "点在圆上" << endl;	}	else if (ret > c.getR()*c.getR()) {
   		cout << "点在圆外" << endl;	}	else {
   		cout << "点在圆内" << endl;	}}void test01() {
   	Point p1;	p1.setXY(3, 4);	Point center;	AdvCircle c1;	center.setXY(0, 0);	c1.setR(1);	c1.setCenter(center);	isInCircle(c1, p1);}void test02() {
   	AdvCircle a;	Point p;	p.setXY(3, 4);	a.setR(2);	Point center;	center.setXY(0, 0);	a.setCenter(center);	int r = a.getR();	a.isInCircle(p);}int main() {
   	test02();	system("pause");	return 0;}
    
   

point.h#pragma once#include
   
    using namespace std;class Point {
   public:	void setXY(int x, int y);	int getX();	int getY();private:	int m_x;	int m_y;};
   

point.cpp#include"point.h"void Point::setXY(int x, int y) {
   	m_x = x;	m_y = y;}int Point::getX() {
   	return m_x;}int Point::getY() {
   	return m_y;}

circle.h#pragma once#include
   
    using namespace std;#include"point.h"class AdvCircle {
   public:	void setR(int r);	int getR();	//设置圆心	void setCenter(Point &p);	//获取圆心	Point getCenter();	//利用成员函数判断点和圆的关系	void isInCircle(Point p);private:	Point m_center;	int m_r;};
   

circle.cpp#include"circle.h"void AdvCircle::setR(int r) {
   	m_r = r;}int AdvCircle::getR() {
   	return m_r;}//设置圆心void AdvCircle::setCenter(Point &p) {
   	m_center = p;}//获取圆心Point AdvCircle::getCenter() {
   	return m_center;}//利用成员函数判断点和圆的关系void AdvCircle::isInCircle(Point p) {
   	double ret = pow((p.getX() - m_center.getX()), 2) + pow((p.getY() - m_center.getY()), 2);	if (ret == m_r*m_r) {
   		cout << "点在圆上" << endl;	}	else if (ret > m_r*m_r) {
   		cout << "点在圆外" << endl;	}	else {
   		cout << "点在圆内" << endl;	}}

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