//TREE
array (
  0 =>
  stdClass::__set_state(array(
     'unit_id' => '5',
     'localunit_id' => '5',
     'name' => 'Transport',
     'parent_id' => '0',
     'id_shop' => '-1',
     'deleted' => '0',
     'parent' => '#',
     'children' =>
    array (
      0 =>
      stdClass::__set_state(array(
         'unit_id' => '2',
         'localunit_id' => '2',
         'name' => 'Seri',
         'parent_id' => '5',
         'id_shop' => '-1',
         'deleted' => '0',
         'parent' => '5',
         'children' =>
        array (
          0 =>
          stdClass::__set_state(array(
             'unit_id' => '1',
             'localunit_id' => '1',
             'name' => 'Cope',
             'parent_id' => '2',
             'id_shop' => '-1',
             'deleted' => '0',
             'parent' => '2',
          )),
        ),
      )),
    ),
  )),
  1 =>
  stdClass::__set_state(array(
     'unit_id' => '19',
     'localunit_id' => '8',
     'name' => 'Top',
     'parent_id' => '0',
     'id_shop' => '-1',
     'deleted' => '0',
     'parent' => '#',
     'children' =>
    array (
      0 =>
      stdClass::__set_state(array(
         'unit_id' => '7',
         'localunit_id' => '7',
         'name' => 'm',
         'parent_id' => '19',
         'id_shop' => '-1',
         'deleted' => '0',
         'parent' => '19',
      )),
    ),
  )),
)

//Iterated
array (
  0 =>
  stdClass::__set_state(array(
     'unit_id' => '1',
     'localunit_id' => '1',
     'name' => 'Cope',
     'parent_id' => '2',
     'id_shop' => '-1',
     'deleted' => '0',
     'parent' => '2',
     'group' => 1,
  )),
  1 =>
  stdClass::__set_state(array(
     'unit_id' => '2',
     'localunit_id' => '2',
     'name' => 'Seri',
     'parent_id' => '5',
     'id_shop' => '-1',
     'deleted' => '0',
     'parent' => '5',
     'group' => 1,
  )),
  2 =>
  stdClass::__set_state(array(
     'unit_id' => '5',
     'localunit_id' => '5',
     'name' => 'Transport',
     'parent_id' => '0',
     'id_shop' => '-1',
     'deleted' => '0',
     'parent' => '#',
     'group' => 1,
  )),
  3 =>
  stdClass::__set_state(array(
     'unit_id' => '7',
     'localunit_id' => '7',
     'name' => 'm',
     'parent_id' => '19',
     'id_shop' => '-1',
     'deleted' => '0',
     'parent' => '19',
     'group' => 1,
  )),
  4 =>
  stdClass::__set_state(array(
     'unit_id' => '19',
     'localunit_id' => '8',
     'name' => 'Top',
     'parent_id' => '0',
     'id_shop' => '-1',
     'deleted' => '0',
     'parent' => '#',
     'group' => 2,
  )),
)

private $testVar=[];
    function flatTree($elements)
    {
        $cnt=0;
        foreach($elements as $element)
        {
            $cnt++;
            if(isset($element->children)){
                $this->flatTree($element->children);
            }

            $tempElement=$element;
            if(isset($tempElement->children))
                unset($tempElement->children);

            $tempElement->group=$cnt;
            $this->testVar[]=$tempElement;
        }
        return ;
    }