[php] - Alberi binari e ordinamento

[filippo.toso]

Studiati questo codice:

<pre>
<?php 

$array = array ( 0 => array ( 'id' => '1', 'name' => 'Nodo1', 'parent' => '0', 'attivo' => '1'),
                      1 => array ( 'id' => '2', 'name' => 'Nodo2', 'parent' => '0', 'attivo' => '1'),
                      2 => array ( 'id' => '3', 'name' => 'Nodo3', 'parent' => '2', 'attivo' => '1'),
                      3 => array ( 'id' => '4', 'name' => 'Nodo4', 'parent' => '3', 'attivo' => '1'));
                      
function tree($nodes, $level = 0) {
    foreach ($nodes as $node) {
        $pre = str_repeat('   ', $level) . '|_ ';
        print("{$pre}{$node['name']}\r\n");
        tree($node['childs'], $level + 1);
    }
}

$items = array();
foreach ($array as $node) {
    $items[$node['id']] = $node;
    $items[$node['id']]['childs'] = array();
}
$items[0] = array('name' => 'root', 'parent' => -1, 'childs' => array());

foreach ($items as &$item) {
    $items[$item['parent']]['childs'][] = & $item;
}

tree($items[0]['childs']);

?>
</pre>