public function testBFS()
{
$Graph = ['A' => ['B', 'C'], 'B' => ['A', 'D'], 'D' => ['B'], 'C' => ['A']];
$this->assertTrue(bfs($Graph, 'A', 'D'));
$this->assertFalse(bfs($Graph, 'A', 'F'));
}
$root->left = new Node(4);
$root->right = new Node(3);
$root->left->left = new Node(6);
$root->left->right = new Node(7);
$root->right->left = new Node(8);
$root->right->right = new Node(9);
function bfs(Node $node)
{
$queue = array($node);
$node->hd = 0;
$output = array();
while (count($queue) > 0) {
$current_node = array_shift($queue);
$output[$current_node->hd][] = $current_node->info;
if ($current_node->left != null) {
$current_node->left->hd = $current_node->hd + 1;
array_push($queue, $current_node->left);
}
if ($current_node->right != NULL) {
$current_node->right->hd = $current_node->hd - 1;
array_push($queue, $current_node->right);
}
}
return $output;
}
$result = bfs($root);
$keys = array_keys($result);
arsort($keys);
foreach ($keys as $key) {
echo implode(' ', $result[$key]), "\n";
}
$dag = array(array(0, 1, 1, 0, 0, 0, 0), array(0, 0, 0, 1, 0, 0, 0), array(0, 0, 0, 0, 1, 0, 0), array(0, 0, 0, 0, 1, 0, 0), array(0, 0, 0, 0, 0, 0, 1), array(0, 0, 0, 0, 0, 0, 1), array(0, 0, 0, 0, 0, 0, 0));
function bfs(&$graph, $start, $visited)
{
// create an empty queue
$q = array();
// initially enqueue only the starting vertex
array_push($q, $start);
$visited[$start] = 1;
echo $start . "\n";
while (count($q)) {
$t = array_shift($q);
foreach ($graph[$t] as $key => $vertex) {
if (!$visited[$key] && $vertex == 1) {
$visited[$key] = 1;
array_push($q, $key);
echo $key . "\t";
}
}
echo "\n";
}
}
function init(&$visited, &$graph)
{
foreach ($graph as $key => $vertex) {
$visited[$key] = 0;
}
}
$visited = array();
init($visited, $dag);
bfs($dag, 4, $visited);
$queue = array();
array_push($queue, $start_vertex);
while (count($queue) > 0) {
$current_vertext = array_shift($queue);
$neighbor = $current_vertext->getConnections();
foreach ($neighbor as $nbr_vertext) {
if ($nbr_vertext['neighbor']->getColor() == 'white') {
$nbr_vertext['neighbor']->setColor('gray');
$nbr_vertext['neighbor']->setDistance($current_vertext->getDistance() + 1);
$nbr_vertext['neighbor']->setPredecessor($current_vertext);
array_push($queue, $nbr_vertext['neighbor']);
}
}
$current_vertext->setColor('black');
}
}
/**
* 목표 단어부터 전임자를 탐색하여 시작 단어까지
*/
function traverse($end_vertex)
{
$vertex = $end_vertex;
while ($vertex->getPredecessor()) {
echo $vertex->getId() . ' <- ';
$vertex = $vertex->getPredecessor();
}
echo $vertex->getId();
}
$word_radder = buildWordLadderGraph('word_source.txt');
bfs($word_radder->getVertex('fool'));
traverse($word_radder->getVertex('sale'));