function GetAllCount($ID,$BLOCK)
   {
      $nav = CIBlockSection::GetByID($ID);
      $navEnd = $res->GetNext();

      $arFilter   =   array(   'IBLOCK_ID'      =>   $BLOCK,
                        'LEFT_MARGIN'   =>   $navEnd['LEFT_MARGIN'],
                        'RIGHT_MARGIN'   =>   $navEnd['RIGHT_MARGIN']
      );

      $sections = CIBlockSection::GetTreeList($arFilter);
      while($ar_dep = $sections->GetNext())
        {
           echo $ar_dep['NAME'].'<br>';
        }  
   }