Last active
April 25, 2019 11:23
-
-
Save max-dark/f39028cc106ed32e8ce1b55a11643b43 to your computer and use it in GitHub Desktop.
restore tree from table
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
<?php | |
/** | |
* @file https://gist.github.com/max-dark/f39028cc106ed32e8ce1b55a11643b43 | |
*/ | |
define('ROOT_NODE', null); | |
/** | |
* восстанавливает дерево по таблице связей | |
* @param array $data | |
* @return array | |
*/ | |
function restore_tree($data) | |
{ | |
$lst = prepare_parents($data); | |
restore_tree_impl($lst[ROOT_NODE], $lst); | |
return $lst[ROOT_NODE]; | |
} | |
/** | |
* восстановление связей родитель->дети | |
* @param array $parent | |
* @param array $data | |
* @return void | |
*/ | |
function restore_tree_impl(&$parent, &$data) { | |
foreach ($parent['child'] as &$child) { | |
// Если текущий ребенок сам является родителем | |
if (array_key_exists($child['id'], $data)) { | |
// восстановить связь | |
$child['child'] = $data[$child['id']]['child']; | |
// проверить детей | |
restore_tree_impl($child, $data); | |
} else { | |
$child['child'] = []; | |
} | |
} | |
} | |
function make($id) { | |
return ['id' => $id, 'title' => '[root]', 'child' => []]; | |
} | |
/** | |
* Создает список узлов, имеющих датей | |
* @param array $data | |
* @return array | |
*/ | |
function prepare_parents($data) { | |
$res = []; | |
foreach ($data as $item) { | |
$parent = $item['parent_id']; | |
if (!array_key_exists($parent, $res)) { | |
$res[$parent] = make($parent); | |
if (array_key_exists($parent, $data)) { | |
$res[$parent]['title'] = $data[$parent]['title']; | |
} | |
} | |
unset($item['parent_id']); | |
array_push($res[$parent]['child'], $item); | |
} | |
return $res; | |
} | |
function show($item, $level) { | |
if ($item['id'] === null) return; | |
while ($level --> 0) { | |
echo '..'; | |
} | |
echo $item['title'].PHP_EOL; | |
} | |
function print_tree($data, $level = -1) { | |
show($data, $level); | |
foreach ($data['child'] as $item) { | |
print_tree($item, $level + 1); | |
} | |
} | |
$data = [ | |
['id'=>0, 'title'=>'Электроника', 'parent_id' => null], | |
['id'=>1, 'title'=>'Компьютеры', 'parent_id' => 0], | |
['id'=>2, 'title'=>'ПК', 'parent_id' => 1], | |
['id'=>3, 'title'=>'Ноутбуки', 'parent_id' => 1], | |
['id'=>4, 'title'=>'Мобильные телефоны', 'parent_id' => 0], | |
['id'=>5, 'title'=>'Бытовая химия', 'parent_id' => null], | |
['id'=>6, 'title'=>'Порошок', 'parent_id' => 5], | |
['id'=>7, 'title'=>'Мыло', 'parent_id' => 5], | |
['id'=>8, 'title'=>'Трансформеры', 'parent_id' => 3], | |
]; | |
$root = restore_tree($data); | |
print_tree($root); |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment