一個高效的數組轉樹結構的演算法實現

標籤：php   var_dump   add   set   parent   _id   nan   node   blog   

<?php// [email protected]function addNode(&$node, &$tree) {    $node_id = $node[‘id‘];    if (!isset($tree[$node_id])) {        $tree[$node_id] = $node;        $tree[$node_id][‘sub‘] = [];        $node[‘ref‘] = & $tree[$node_id];    }}function addNodeWithParent(&$node, &$nodes, &$tree) {    $pid = $node[‘pid‘];    if ($pid == 0) {        addNode($node, $tree);    } else {        $pnode = & $nodes[$pid];        if (!isset($pnode[‘ref‘])) {            addNodeWithParent($pnode, $nodes, $tree);        }        addNode($node, $pnode[‘ref‘][‘sub‘]);    }}
// 數組可以無序，必須要索引$nodes = [    5 => [‘id‘ => 5, ‘name‘ => ‘node5‘, ‘pid‘ => 3],    1 => [‘id‘ => 1, ‘name‘ => ‘node1‘, ‘pid‘ => 0],    2 => [‘id‘ => 2, ‘name‘ => ‘node2‘, ‘pid‘ => 0],    3 => [‘id‘ => 3, ‘name‘ => ‘node3‘, ‘pid‘ => 1],    4 => [‘id‘ => 4, ‘name‘ => ‘node4‘, ‘pid‘ => 1],    6 => [‘id‘ => 6, ‘name‘ => ‘node6‘, ‘pid‘ => 2],    7 => [‘id‘ => 7, ‘name‘ => ‘node7‘, ‘pid‘ => 2],    8 => [‘id‘ => 8, ‘name‘ => ‘node8‘, ‘pid‘ => 0],];$tree = [];foreach($nodes as $i => &$node) {    addNodeWithParent($node, $nodes, $tree);}var_dump($tree);

 

一個高效的數組轉樹結構的演算法實現