Get the path relationship of infinite categories of left and right values

Recently, I need something that can display something like
1 > 2
1 > 2 > 3
1 > 2 > 3 > 4
. I don’t know the algorithm, so I just took a lot of detours. Of course, I hope you have a better way. Tucao is welcome.

 public function getPaths($nodes)
 {
 $levels = $paths = array();
 // Reorganize array levels
 foreach ($nodes as $id => $node)
 {
 $levels[ $node['level']][$id] = $node;
 }
 for ($i = 0; $i < count($levels); $i++)
 {
 if (is_array($levels[$ i]))
 {
 foreach ($levels[$i] as $level)
 {
 $id = $level['id'];
 $parent_id = $level['parent_id'];
 $parent = $ paths[$parent_id];
 // There is a parent and appended to the current node
 if ($parent)
 {
 $paths[$id] = $parent;
 $paths[$id][] = $level[ 'id'];
 }
 else
 {
 $paths[$id][] = $level['id'];
 }
 }
 }
 }
 return $paths;
 }