// A very simple class point with public data representation.
// An incomplete sketch.
// This version uses polar representation.
// NOT RECOMMENDED because of public data representation.

using System;

public class Point {
  public double radius, angle;

  public Point(double x, double y){
    radius = ...
    angle = ...
  }

  public void Move(double dx, double dy){
    radius = ...
    angle = ...
  }

  public void Rotate(double angle){
    this.angle += angle;
  }

  public override string ToString(){
    ...
  }



  private static double RadiusGivenXy(double x, double y){
    return Math.Sqrt(x * x + y * y);
  }

  private static double AngleGivenXy(double x, double y){
    return Math.Atan2(y,x);
  }

  private static double XGivenRadiusAngle(double r, double a){
    return r * Math.Cos(a);
  }

  private static double YGivenRadiusAngle(double r, double a){
    return r * Math.Sin(a);
  }


}