public class LoopDemo3 {
   public static void main (String[] argh) {
      for (int i = 0; i < 6; i = i+1) {
         System.out.print(i + ". ");
         
         for (int j = 0; j < i; j++) {
            System.out.print(j + " ");
         }
         
         System.out.println();
      }
   }
}

/*

public class LoopDemo2 {
   public static void main (String[] argh) {
      for (int i = 0; i < 3; i++) {
         System.out.println(i);
      }
   }
}

*/