main()
{						/* Beginning of the first level block */
   int A, B;
   
   A = 1;
   B = A * 2;
   if(A == B)
   {	 				/* Beginning of the second level block */
      while(A < 10)
      {	 			/* Beginning of the third level block */
         A++;
      }	    		/* End of the third level block */
   }	    			/* End of the second level block */
}	    				/* End of the first level block */