用类求两点间的距离

设计一个用来表示直角坐标系的Location类，在主程序中创建类Location的两个对象A和B，要求A的坐标点在第3象限，B的坐标点在第2象限，分别采用成员函数和友元函数计算给定两个坐标点之间的距离，要求按如下格式输出结果：

A(x1,y1), B(x2,y2),

Distance1=d1

#include<iostream>
#include<cmath>
using namespace std;
class Location
{
  public:
    Location(double a,double b);//构造函数; 
    double getx();
    double gety();
    double distance(Location &d);//成员函数 
    friend double distance1(Location &,Location &);//友元函数; 
  private:
    double x,y;
};
Location::Location(double a,double b)//构造函数定义; 
{
  x=a;
  y=b;
}
double Location:: getx()
{
  return x;
}
double Location::gety()
{
  return y;
}
double Location::distance(Location &d)
{
  double d1;
  d1=sqrt((this->x-d.x)*(this->x-d.x)+(this->y-d.y)*(this->y-d.y));
  cout<<"Distance1="<<d1<<endl;
  return 0;
}
double distance1(Location &a,Location &b)
{
  double d2;
  d2=sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y));
  cout<<"Distance2="<<d2<<endl;
  return 0;
}
int main()
{
  Location A(-1,-1);
  Location B(-1,1);
  cout<<"A("<<A.getx()<<","<<A.gety()<<endl;
  A.distance(B);
  distance(A,B);
  return 0;
}