SecretMessage.java

Below is the syntax highlighted version of SecretMessage.java.

/**********************************************************************
 * Compile: javac SecretMessage.java
 * Execute: java SecretMessage 7
 **********************************************************************/

public class SecretMessage {

  public static void main(String[] args) { 
    int N = Integer.parseInt(args[0]);
    for (int i = -3*N/2; i <= N; i++) {
      for (int j = -3*N/2; j <= 3*N/2; j++) {

          // inside either diamond or two circles
          if ( (Math.abs(i) + Math.abs(j) < N)
              || ((-N/2-i) * (-N/2-i) + ( N/2-j) * ( N/2-j) <= N*N/2)
              || ((-N/2-i) * (-N/2-i) + (-N/2-j) * (-N/2-j) <= N*N/2)
             )
                  System.out.print("* ");
          else    System.out.print(". ");
       }
       System.out.println();
    }
  }
}