C++ 实现点与圆的位置关系

浅浅的花香味﹌ 2022-05-29 09:58 118阅读 0赞

C++ 实现点与圆的位置关系

//maincircle
    
    #include<iostream>
    #include"circle.h"
    #include"point.h"
    using namespace std;
    int main()
    {
        circle c1;
        point p1;
        c1.getcircle( 0, 0, 4 );
        p1.getpoint( 2, 2 ) ;
        cout<<c1.judge1( p1.getx(), p1.gety() )<<endl;
        cout<<c1.judge2(p1)<<endl;
    
        return 0;
    }
    //point.h
    #pragma once
    class point
    {
    public:
        void getpoint(double x,double y);
        double getx();
        double gety();
    public:
        double x1;
        double y1;
    };
    
    //point.cpp
    #include "point.h"
    void point::getpoint(double x,double y)
    {
        x1 = x;
        y1 = y;
    }
    
    double point::getx()
    {
        return x1;
    }
    
    double point::gety()
    {
        return y1;
    }
    //circle.h
    #pragma once
    #include"point.h"
    class circle
    {
    public:
        void getcircle(double x,double y, double r);
        char* judge1( double x,double y);
        /*char* judge2( point &p);*/
    private :
        double x0;
        double y0;
        double r1;
    };
    //circle.cpp
    #include "circle.h"
    void circle:: getcircle(double x,double y, double r)
    {
        x0=x;
        y0=y;
        r1=r;
    }
    char* circle::judge1( double x,double y)
    {
        double s =(x0 - x)*(x0 - x) + (y0 - y)*(y0 - y) - r1*r1;
        if( s > 0 )
        {
            return "outside the circle"
        }
        else
        {
            if( s == 0)
            {
                return " on the circle"
            }
            else return " in the circle"
        }
    }
    
    char* circle::judge2( point & p)
    {
        double s =(x0 - p.getx())*(x0 - p.getx()) + (y0 - p.gety())*(y0 - p.gety()) - r1*r1;
        if( s > 0 )
        {
            return "outside the circle ";
        }
        else
        {
            if( s == 0)
            {
                return " on the circle";
            }
            else return " in the circle ";
        }
    }

**圆心坐标为（0，0），半径为4**   
**（1）点的坐标为(2,2)**  
![Image 1][]  
**\*（2）点的坐标为(0,4)**  
![Image 1][]  
**（3）点的坐标为(8,4)**  
![Image 1][]  
**judge1()和judge2()同时放开后**  
![Image 1][]

[Image 1]: