Distance between two points

/* Distance Between Two Points*/
/*       Language: C++        */



#include <iostream.h>
#include <conio.h>
#include <math.h>

class coordinates
{
    float a,b;

    public:
        coordinates(float x,float y)
        {
            a=x;
            b=y;
        }
        friend float distance(coordinates &point1,coordinates &point2);
};


float distance(coordinates &point1,coordinates &point2)
{
    float distance;
    float temp;
    temp=((point1.a-point2.a)*(point1.a-point2.a))+((point1.b-point2.b)*(point1.b-point2.b));
    distance=sqrt(temp);
    return distance;
}


int main()
{
    system("cls");
    float a1,b1;
    float a2,b2;
    cout<<"\nEnter Coordinates of Point 1: \n";
    cin>>a1>>b1;
    cout<<"\nEnter Coordinates of Point 2: \n";
    cin>>a2>>b2;
    coordinates point1(a1,b1);
    coordinates point2(a2,b2);
    float distance_result=distance(point1,point2);
    cout<<"\n\nDistance between the two given points is: "<<distance_result;
    getch();
    return 0;
}