#include <iostream>
#include <cmath>

using namespace std;

class Point
{
public:
    Point (float a,float b)
    {
        x = a;
        y = b;
    }
    void printf();

    float getX() const;

    float getY() const;

    friend Point middle(const Point &p1,const Point &p2);//友元函数

private:
    float x;
    float y;
};

//友元函数没有this指针，它可以直接访问Point类中的public、private成员
Point middle(const Point &p1,const Point &p2)
{
    cout << "学校坐标为:" << "(" << p1.getX()/2 << "," << p2.getY()/2 << ")" << endl;
}

void  Point::printf()
{
     cout << "小明家坐标位置(0,0)" << endl;
}

//计算距离
float dist(Point &p1, Point &p2)
{
    float distance = sqrt(p1.getX()*p1.getX() + p2.getY()*p2.getY());
    cout << "小明家与小志家距离为：" << distance << endl;
}

//获取X坐标
float Point::getX() const
{
    return x;
}

//获取Y坐标
float Point::getY() const
{
    return y;
}


int main()
{
    float a ,b;
    cout << "请您输入小志的坐标: " ;
    cin >> a >>b;

   Point point(a,b);
   point.printf();
   cout << "小志家坐标为：" << "(" << a << "," << b << ")"<< endl;

   middle(point,point);
   dist(point,point);


    return 0;
}

要是看不懂的话，可以问我

求距离的代码如下，采纳后补充其他内容：

#include <iostream>
#include <math>
using namespace std;
class point 
{
public:
point(int xx=0,int yy=0){X=xx;Y=yy;}
int getX(){return X;}
int getY(){return Y;}
friend float dist(point &a, point &b);
private:
int X,Y;
};
float dist(point &p1,point &p2)
{
double x=double(p1.X-p2.X);
double y=double(p1.Y-p2.Y);
return float(sqrt(x*x+y*y));
}
int main()
{
point myp1(0,0),myp2(4,4);
cout<<"距离是："<< dist(myp1,myp2) << endl;
}