67 lines
1.8 KiB
PHP
67 lines
1.8 KiB
PHP
<?php
|
|
|
|
namespace Graphp\Algorithms\Search;
|
|
|
|
use Fhaculty\Graph\Vertex;
|
|
use Fhaculty\Graph\Set\Vertices;
|
|
|
|
class DepthFirst extends Base1
|
|
{
|
|
/**
|
|
*
|
|
* calculates the recursive algorithm
|
|
*
|
|
* fills $this->visitedVertices
|
|
*
|
|
* @param Vertex $vertex
|
|
*/
|
|
private function recursiveDepthFirstSearch(Vertex $vertex, array & $visitedVertices)
|
|
{
|
|
// If I didn't visited this vertex before
|
|
if (!isset($visitedVertices[$vertex->getId()])) {
|
|
// Add Vertex to already visited vertices
|
|
$visitedVertices[$vertex->getId()] = $vertex;
|
|
|
|
// Get next vertices
|
|
$nextVertices = $vertex->getVerticesEdgeTo();
|
|
|
|
foreach ($nextVertices as $nextVertix) {
|
|
// recursive call for next vertices
|
|
$this->recursiveDepthFirstSearch($nextVertix, $visitedVertices);
|
|
}
|
|
}
|
|
}
|
|
|
|
private function iterativeDepthFirstSearch(Vertex $vertex)
|
|
{
|
|
$visited = array();
|
|
$todo = array($vertex);
|
|
while ($vertex = array_shift($todo)) {
|
|
if (!isset($visited[$vertex->getId()])) {
|
|
$visited[$vertex->getId()] = $vertex;
|
|
|
|
foreach (array_reverse($this->getVerticesAdjacent($vertex)->getMap(), true) as $vid => $nextVertex) {
|
|
$todo[] = $nextVertex;
|
|
}
|
|
}
|
|
}
|
|
|
|
return new Vertices($visited);
|
|
}
|
|
|
|
/**
|
|
* calculates a recursive depth-first search
|
|
*
|
|
* @return Vertices
|
|
*/
|
|
public function getVertices()
|
|
{
|
|
return $this->iterativeDepthFirstSearch($this->vertex);
|
|
|
|
$visitedVertices = array();
|
|
$this->recursiveDepthFirstSearch($this->vertex, $visitedVertices);
|
|
|
|
return $visitedVertices;
|
|
}
|
|
}
|