This is the question:

Write a c++ program that accepts the rectangular coordinates of two points (x,y) and (x2,y2), calculates the distance of each point from the origin and calculates the distance between the two points. The distance, d, between two points is given by this formula.

This is what I have thus far. What Im I missing

#include<iostream>

#include<cmath>

using namespace std;

void Cylinder( double radius, double length, double volume, double surface)

{

volume = 3.14 * pow(radius,2) * length;

surface = 2 * 3.14 * radius* length;

return ;

}

int main()

{

double r, l , v, s;

cout << " Please enter the radius ( in cm) of the cylinder : " endl;

cin >> r;

cout << " Please enter length ( in cm) of cylinder: " endl;

cin >> l;

Cylinder ( double radius, double length, double volume, double surface);

cout << " Your volume is: "<< v << " and your surface is: " << s << endl;

return 0;

}