import java.awt.Color;
public class PolyClient { 

  public static void main(String[] args) {

    //-----------------------------------------------------------------
    // Scale window to 40x40 and draw gray 'reference' lines
    //-----------------------------------------------------------------
    StdDraw.setXscale(0,40);
    StdDraw.setYscale(0,40);
    
    // draw the quartering lines for 'reference' in gray
    StdDraw.setPenColor( Color.GRAY );
    StdDraw.line( 20,0   ,   20,40 ); // vertical
    StdDraw.line(  0,20  ,   40,20 ); // horizontal

    //-----------------------------------------------------------------
    // Center a simplified spoked wheel in upper left quarter of window
    //   all shapes drawn should be black
    //-----------------------------------------------------------------
    double x, y, radius;
    StdDraw.setPenColor( Color.BLACK );

    // where is center of upper left quarter?
    ??? -1- ???
    StdDraw.circle( x,y, radius);

    //.......................................................
    // When calculating the endpoints of the lines
    //    do not use any "hard-coded" numberical literals
    //    instead use only variable names
    //.......................................................
    double x1,y1,x2,y2;

    // where are endpts of vertical line in circle?
    ??? -2- ???
    StdDraw.line( x1,y1,  x2,y2 );
    
    // where are endpts of horizontal line in circle?
    ??? -3- ???
    StdDraw.line( x1,y1,  x2,y2 );
  }
}