public class Checkerboard {
  public static void main (String[] args) {
    int N = Integer.parseInt(args[0]);
    for (int x = 0; x < N; x++) {
      if (x % 2 == 0) {
        System.out.print(" ");
      }
      for (int y = 0; y < N; y++) {
        System.out.print("* ");
      }
      System.out.println ();
    }
  }
}