Checker Board java in pgm

CheckerBoard.java

public class CheckerBoard

{

    public static void main(String[] args)

 {

        int N = Integer.parseInt(args[0]);

        StdDraw.setXscale(0, N);

        StdDraw.setYscale(0, N);

        for (int i = 0; i < N; i++)

       {

            for (int j = 0; j < N; j++)

            {

                if ((i + j) % 2 != 0)

                StdDraw.setPenColor(StdDraw.BLACK);

                else                 

                StdDraw.setPenColor(StdDraw.RED);

                StdDraw.filledSquare(i + .5, j + .5, .5);

            }

        }

        StdDraw.show();

    }

}