mirror of
https://github.com/Karaka-Management/phpOMS.git
synced 2026-01-11 17:58:41 +00:00
911 lines
20 KiB
PHP
Executable File
911 lines
20 KiB
PHP
Executable File
<?php
|
|
/**
|
|
* Karaka
|
|
*
|
|
* PHP Version 8.1
|
|
*
|
|
* @package phpOMS\Stdlib\Graph
|
|
* @copyright Dennis Eichhorn
|
|
* @license OMS License 1.0
|
|
* @version 1.0.0
|
|
* @link https://jingga.app
|
|
*/
|
|
declare(strict_types=1);
|
|
|
|
namespace phpOMS\Stdlib\Graph;
|
|
|
|
/**
|
|
* Graph class.
|
|
*
|
|
* @package phpOMS\Stdlib\Graph
|
|
* @license OMS License 1.0
|
|
* @link https://jingga.app
|
|
* @since 1.0.0
|
|
*/
|
|
class Graph
|
|
{
|
|
/**
|
|
* Nodes.
|
|
*
|
|
* @var Node[]
|
|
* @since 1.0.0
|
|
*/
|
|
protected array $nodes = [];
|
|
|
|
/**
|
|
* Directed
|
|
*
|
|
* @var bool
|
|
* @since 1.0.0
|
|
*/
|
|
protected bool $isDirected = false;
|
|
|
|
/**
|
|
* Set node to graph.
|
|
*
|
|
* @param Node $node Graph node
|
|
*
|
|
* @return Graph
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function setNode(Node $node) : self
|
|
{
|
|
$this->nodes[$node->getId()] = $node;
|
|
|
|
return $this;
|
|
}
|
|
|
|
/**
|
|
* Get graph node
|
|
*
|
|
* @param int|string $key Node key
|
|
*
|
|
* @return null|Node
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getNode(int | string $key) : ?Node
|
|
{
|
|
return $this->nodes[$key] ?? null;
|
|
}
|
|
|
|
/**
|
|
* Define a relationship between two nodes
|
|
*
|
|
* @param Node $node1 First node
|
|
* @param Node $node2 Second node
|
|
*
|
|
* @return Edge
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function setNodeRelative(Node $node1, Node $node2) : Edge
|
|
{
|
|
return $node1->setNodeRelative($node2, null, true);
|
|
}
|
|
|
|
/**
|
|
* Graph has node
|
|
*
|
|
* @param int|string $key Node key
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function hasNode(int | string $key) : bool
|
|
{
|
|
return isset($this->nodes[$key]);
|
|
}
|
|
|
|
/**
|
|
* Get graph nodes
|
|
*
|
|
* @return Node[]
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getNodes() : array
|
|
{
|
|
return $this->nodes;
|
|
}
|
|
|
|
/**
|
|
* Is directed graph
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function isDirected() : bool
|
|
{
|
|
return $this->isDirected;
|
|
}
|
|
|
|
/**
|
|
* Set graph directed
|
|
*
|
|
* @param bool $directed Is directed?
|
|
*
|
|
* @return void
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function setDirected(bool $directed) : void
|
|
{
|
|
$this->isDirected = $directed;
|
|
}
|
|
|
|
/**
|
|
* Get graph/edge costs
|
|
*
|
|
* @return int|float
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getCost() : int | float
|
|
{
|
|
$edges = $this->getEdges();
|
|
$costs = 0;
|
|
|
|
foreach ($edges as $edge) {
|
|
$costs += $edge->getWeight();
|
|
}
|
|
|
|
return $costs;
|
|
}
|
|
|
|
/**
|
|
* Get graph edges
|
|
*
|
|
* @return Edge[]
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getEdges() : array
|
|
{
|
|
$edges = [];
|
|
|
|
foreach ($this->nodes as $node) {
|
|
$nodeEdges = $node->getEdges();
|
|
|
|
foreach ($nodeEdges as $edge) {
|
|
if (!isset($edges[$edge->getNode1()->getId() . ':' . $edge->getNode2()->getId()])
|
|
&& !isset($edges[$edge->getNode2()->getId() . ':' . $edge->getNode1()->getId()])
|
|
) {
|
|
$edges[$edge->getNode1()->getId() . ':' . $edge->getNode2()->getId()] = $edge;
|
|
}
|
|
}
|
|
}
|
|
|
|
return $edges;
|
|
}
|
|
|
|
/**
|
|
* Get the edge between two nodes
|
|
*
|
|
* @param string $id1 Node id
|
|
* @param string $id2 Node id
|
|
*
|
|
* @return null|Edge
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getEdge(string $id1, string $id2) : ?Edge
|
|
{
|
|
foreach ($this->nodes as $node) {
|
|
if ($node->getId() !== $id1 && $node->getId() !== $id2) {
|
|
continue;
|
|
}
|
|
|
|
$nodeEdges = $node->getEdges();
|
|
|
|
foreach ($nodeEdges as $edge) {
|
|
if (($edge->getNode1()->getId() === $id1 || $edge->getNode1()->getId() === $id2)
|
|
&& ($edge->getNode2()->getId() === $id1 || $edge->getNode2()->getId() === $id2)
|
|
) {
|
|
return $edge;
|
|
}
|
|
}
|
|
}
|
|
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* Get all bridges.
|
|
*
|
|
* @return Edge[]
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getBridges() : array
|
|
{
|
|
$visited = [];
|
|
$parent = [];
|
|
$discovery = [];
|
|
$low = [];
|
|
$index = 0;
|
|
$bridges = [];
|
|
|
|
foreach ($this->nodes as $i => $node) {
|
|
if (!isset($visited[$i]) || $visited[$i] === false) {
|
|
$this->bridgesDepthFirstSearch($node, $visited, $discovery, $low, $parent, $index, $bridges);
|
|
}
|
|
}
|
|
|
|
return $bridges;
|
|
}
|
|
|
|
/**
|
|
* Fill bridge array
|
|
*
|
|
* @param Node $node Node to check bridge for
|
|
* @param bool[] $visited Visited nodes
|
|
* @param int[] $discovery Discovered
|
|
* @param int[] $low Lowest preorder of any vertex connected to ?
|
|
* @param Node[] $parent Parent node
|
|
* @param int $index Node index
|
|
* @param Edge[] $bridges Edges which represent bridges
|
|
*
|
|
* @return void
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
private function bridgesDepthFirstSearch(
|
|
Node $node,
|
|
array &$visited,
|
|
array &$discovery,
|
|
array &$low,
|
|
array &$parent,
|
|
int &$index,
|
|
array &$bridges
|
|
) : void
|
|
{
|
|
$id = $node->getId();
|
|
$visited[$id] = true;
|
|
|
|
++$index;
|
|
|
|
$discovery[$id] = $index;
|
|
$low[$id] = $index;
|
|
|
|
$edges = $this->nodes[$id]->getEdges();
|
|
foreach ($edges as $edge) {
|
|
$neighbor = !$edge->getNode1()->isEqual($node) ? $edge->getNode1() : $edge->getNode2();
|
|
|
|
if (!isset($visited[$neighbor->getId()]) || !$visited[$neighbor->getId()]) {
|
|
$parent[$neighbor->getId()] = $node;
|
|
|
|
$this->bridgesDepthFirstSearch($neighbor, $visited, $discovery, $low, $parent, $index, $bridges);
|
|
|
|
$low[$id] = \min($low[$id], $low[$neighbor->getId()]);
|
|
|
|
if ($low[$neighbor->getId()] > $discovery[$id]) {
|
|
$bridges[] = $edge;
|
|
}
|
|
} elseif (isset($parent[$id]) && !$neighbor->isEqual($parent[$id])) {
|
|
$low[$id] = \min($low[$id], $discovery[$neighbor->getId()]);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Get minimal spanning tree using Kruskal's algorithm.
|
|
*
|
|
* @return Graph
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getKruskalMinimalSpanningTree() : self
|
|
{
|
|
$graph = new self();
|
|
$edges = $this->getEdges();
|
|
|
|
\usort($edges, Edge::class . '::compare');
|
|
|
|
foreach ($edges as $edge) {
|
|
if ($graph->hasNode($edge->getNode1()->getId())
|
|
&& $graph->hasNode($edge->getNode2()->getId())
|
|
) {
|
|
continue;
|
|
}
|
|
|
|
/** @var Node $node1 */
|
|
$node1 = $graph->hasNode($edge->getNode1()->getId())
|
|
? $graph->getNode($edge->getNode1()->getId())
|
|
: clone $edge->getNode1();
|
|
|
|
/** @var Node $node2 */
|
|
$node2 = $graph->hasNode($edge->getNode2()->getId())
|
|
? $graph->getNode($edge->getNode2()->getId())
|
|
: clone $edge->getNode2();
|
|
|
|
if (!$graph->hasNode($node1->getId())) {
|
|
$node1->removeEdges();
|
|
$graph->setNode($node1);
|
|
}
|
|
|
|
if (!$graph->hasNode($node2->getId())) {
|
|
$node2->removeEdges();
|
|
$graph->setNode($node2);
|
|
}
|
|
|
|
$node1->setNodeRelative($node2)
|
|
->setWeight($this->getEdge(
|
|
$node1->getId(),
|
|
$node2->getId()
|
|
)?->getWeight() ?? 0.0
|
|
);
|
|
}
|
|
|
|
return $graph;
|
|
}
|
|
|
|
/**
|
|
* Has cycle in graph.
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function hasCycle() : bool
|
|
{
|
|
return $this->isDirected ? $this->hasCycleDirected() : $this->hasCycleUndirected();
|
|
}
|
|
|
|
/**
|
|
* Has cycle in directed graph.
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
private function hasCycleDirected() : bool
|
|
{
|
|
$visited = [];
|
|
$recStack = [];
|
|
|
|
foreach ($this->nodes as $node) {
|
|
if ($this->hasDirectedCyclicUtil($node->getId(), $visited, $recStack)) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Has cycle in directed graph.
|
|
*
|
|
* @param string $node Node name
|
|
* @param array $visited Visited nodes
|
|
* @param array $stack Recursion stack
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
private function hasDirectedCyclicUtil(string $node, array &$visited, array &$stack) : bool
|
|
{
|
|
if (isset($visited[$node]) && $visited[$node]) {
|
|
$stack[$node] = false;
|
|
|
|
return false;
|
|
}
|
|
|
|
$visited[$node] = true;
|
|
$stack[$node] = true;
|
|
|
|
$neighbors = $this->nodes[$node]->getNeighbors();
|
|
foreach ($neighbors as $neighbor) {
|
|
if ((!isset($visited[$neighbor->getId()]) || !$visited[$neighbor->getId()])
|
|
&& $this->hasDirectedCyclicUtil($neighbor->getId(), $visited, $stack)
|
|
) {
|
|
return true;
|
|
} elseif (isset($stack[$neighbor->getId()]) && $stack[$neighbor->getId()]) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
$stack[$node] = false;
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Has cycle in undirected graph.
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
private function hasCycleUndirected() : bool
|
|
{
|
|
$visited = [];
|
|
|
|
foreach ($this->nodes as $node) {
|
|
if (!isset($visited[$node->getId()]) && $this->hasUndirectedCyclicUtil($node->getId(), $visited, null)) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Has cycle in undirected graph.
|
|
*
|
|
* @param string $node Node name
|
|
* @param array $visited Visited nodes
|
|
* @param null|string $parent Parent node
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
private function hasUndirectedCyclicUtil(string $node, array &$visited, ?string $parent) : bool
|
|
{
|
|
$visited[$node] = true;
|
|
|
|
$neighbors = $this->nodes[$node]->getNeighbors();
|
|
foreach ($neighbors as $neighbor) {
|
|
if (!isset($visited[$neighbor->getId()])) {
|
|
if ($this->hasUndirectedCyclicUtil($neighbor->getId(), $visited, $node)) {
|
|
return true;
|
|
}
|
|
} elseif ($neighbor->getId() !== $parent) {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Get shortest path using Floyd Warschall algorithm.
|
|
*
|
|
* @return array
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getFloydWarshallShortestPath() : array
|
|
{
|
|
return [];
|
|
}
|
|
|
|
/**
|
|
* Get shortest path using Dijkstra algorithm.
|
|
*
|
|
* @return array
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getDijkstraShortestPath() : array
|
|
{
|
|
return [];
|
|
}
|
|
|
|
/**
|
|
* Perform depth first traversal
|
|
*
|
|
* @param Node $node1 Graph node
|
|
* @param Node $node2 Graph node
|
|
* @param array $visited Is the node already visited
|
|
* @param array $path Array of nodes (a path through the graph = connected nodes)
|
|
* @param array $paths Array of paths (all identified paths)
|
|
*
|
|
* @return void
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
private function depthFirstTraversal(
|
|
Node $node1,
|
|
Node $node2 = null,
|
|
array &$visited,
|
|
array &$path,
|
|
array &$paths
|
|
) : void
|
|
{
|
|
$visited[$node1->getId()] = true;
|
|
|
|
if ($node2 !== null && $node1->isEqual($node2)) {
|
|
$paths[] = $path;
|
|
}
|
|
|
|
$neighbors = $node1->getNeighbors();
|
|
foreach ($neighbors as $neighbor) {
|
|
if (!isset($visited[$neighbor->getId()]) || !$visited[$neighbor->getId()]) {
|
|
$path[] = $neighbor;
|
|
$this->depthFirstTraversal($neighbor, $node2, $visited, $path, $paths);
|
|
\array_pop($path);
|
|
}
|
|
}
|
|
|
|
$visited[$node1->getId()] = false;
|
|
}
|
|
|
|
/**
|
|
* Find all reachable nodes with depth first traversal (iterative)
|
|
*
|
|
* Includes the node itself
|
|
*
|
|
* @param int|string|Node $node1 Graph node
|
|
*
|
|
* @return Node[]
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function findAllReachableNodesDFS(int | string | Node $node1) : array
|
|
{
|
|
$nodes = [];
|
|
|
|
if (!($node1 instanceof Node)) {
|
|
$node1 = $this->getNode($node1);
|
|
}
|
|
|
|
if ($node1 === null) {
|
|
return $nodes;
|
|
}
|
|
|
|
$visited = [];
|
|
$stack = [$node1];
|
|
|
|
while (!empty($stack)) {
|
|
$cNode = \array_pop($stack);
|
|
if (isset($visited[$cNode->getId()]) && $visited[$cNode->getId()] === true) {
|
|
continue;
|
|
}
|
|
|
|
$nodes[] = $cNode;
|
|
$visited[$cNode->getId()] = true;
|
|
|
|
$neighbors = $cNode->getNeighbors();
|
|
foreach ($neighbors as $neighbor) {
|
|
if (!isset($visited[$neighbor->getId()]) || $visited[$neighbor->getId()] === false) {
|
|
$stack[] = $neighbor;
|
|
}
|
|
}
|
|
}
|
|
|
|
return $nodes;
|
|
}
|
|
|
|
/**
|
|
* Perform breadth first traversal.
|
|
*
|
|
* @return array
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function breadthFirstTraversal() : array
|
|
{
|
|
return [];
|
|
}
|
|
|
|
/**
|
|
* Get longest path in graph.
|
|
*
|
|
* @return Node[]
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function longestPath() : array
|
|
{
|
|
return [];
|
|
}
|
|
|
|
/**
|
|
* Get all paths between two nodes
|
|
* Inclides end node, but not start node in the paths
|
|
*
|
|
* @param int|string|Node $node1 Graph node
|
|
* @param int|string|Node $node2 Graph node
|
|
*
|
|
* @return array<int, Node[]>
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getAllPathsBetweenNodes(int | string | Node $node1, int | string | Node $node2) : array
|
|
{
|
|
if (!($node1 instanceof Node)) {
|
|
$node1 = $this->getNode($node1);
|
|
}
|
|
|
|
if (!($node2 instanceof Node)) {
|
|
$node2 = $this->getNode($node2);
|
|
}
|
|
|
|
if ($node1 === null || $node2 === null) {
|
|
return [];
|
|
}
|
|
|
|
$path = [];
|
|
$paths = [];
|
|
$visited = [];
|
|
|
|
$this->depthFirstTraversal($node1, $node2, $visited, $path, $paths);
|
|
|
|
return $paths;
|
|
}
|
|
|
|
/**
|
|
* Count possible paths between two nodes.
|
|
*
|
|
* @param int|string|Node $node1 Graph node
|
|
* @param int|string|Node $node2 Graph node
|
|
*
|
|
* @return int
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function countAllPathsBetweenNodes(int | string | Node $node1, int | string | Node $node2) : int
|
|
{
|
|
return \count($this->getAllPathsBetweenNodes($node1, $node2));
|
|
}
|
|
|
|
/**
|
|
* Get longest path between two nodes.
|
|
*
|
|
* @param int|string|Node $node1 Graph node
|
|
* @param int|string|Node $node2 Graph node
|
|
*
|
|
* @return Node[]
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function longestPathBetweenNodes(int | string | Node $node1, int | string | Node $node2) : array
|
|
{
|
|
if (!($node1 instanceof Node)) {
|
|
$node1 = $this->getNode($node1);
|
|
}
|
|
|
|
if (!($node2 instanceof Node)) {
|
|
$node2 = $this->getNode($node2);
|
|
}
|
|
|
|
if ($node1 === null || $node2 === null) {
|
|
return [];
|
|
}
|
|
|
|
$paths = $this->getAllPathsBetweenNodes($node1, $node2);
|
|
|
|
if (empty($paths)) {
|
|
return [];
|
|
}
|
|
|
|
$mostNodes = 0;
|
|
$mostNodesCount = 0;
|
|
foreach ($paths as $key => $path) {
|
|
$edges[$key] = 0;
|
|
$nodeCount = 0;
|
|
foreach ($path as $node) {
|
|
if ($node1->getEdgeByNeighbor($node) === null) {
|
|
continue;
|
|
}
|
|
|
|
$edges[$key] += $node1->getEdgeByNeighbor($node)->getWeight();
|
|
++$nodeCount;
|
|
}
|
|
|
|
if ($nodeCount > $mostNodesCount) {
|
|
$mostNodesCount = $nodeCount;
|
|
$mostNodes = $key;
|
|
}
|
|
}
|
|
|
|
if (\array_sum($edges) > 0.0) {
|
|
\arsort($edges);
|
|
|
|
return $paths[\array_key_first($edges)];
|
|
}
|
|
|
|
return $paths[$mostNodes];
|
|
}
|
|
|
|
/**
|
|
* Get shortest path between two nodes.
|
|
*
|
|
* @param int|string|Node $node1 Graph node
|
|
* @param int|string|Node $node2 Graph node
|
|
*
|
|
* @return Node[]
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function shortestPathBetweenNodes(int | string | Node $node1, int | string | Node $node2) : array
|
|
{
|
|
if (!($node1 instanceof Node)) {
|
|
$node1 = $this->getNode($node1);
|
|
}
|
|
|
|
if (!($node2 instanceof Node)) {
|
|
$node2 = $this->getNode($node2);
|
|
}
|
|
|
|
if ($node1 === null || $node2 === null) {
|
|
return [];
|
|
}
|
|
|
|
$paths = $this->getAllPathsBetweenNodes($node1, $node2);
|
|
|
|
$edges = [];
|
|
$leastNodes = 0;
|
|
$leastNodesCount = \PHP_INT_MAX;
|
|
foreach ($paths as $key => $path) {
|
|
$edges[$key] = 0;
|
|
$nodeCount = 0;
|
|
foreach ($path as $node) {
|
|
if ($node1->getEdgeByNeighbor($node) === null) {
|
|
continue;
|
|
}
|
|
|
|
$edges[$key] += $node1->getEdgeByNeighbor($node)->getWeight();
|
|
++$nodeCount;
|
|
}
|
|
|
|
if ($nodeCount < $leastNodesCount && $nodeCount > 0) {
|
|
$leastNodesCount = $nodeCount;
|
|
$leastNodes = $key;
|
|
}
|
|
}
|
|
|
|
if (\array_sum($edges) > 0.0) {
|
|
\asort($edges);
|
|
|
|
return $paths[\array_key_first($edges)];
|
|
}
|
|
|
|
return $paths[$leastNodes];
|
|
}
|
|
|
|
/**
|
|
* Get order of the graph.
|
|
*
|
|
* The order of a graph is the amount of nodes it contains.
|
|
*
|
|
* @return int
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getOrder() : int
|
|
{
|
|
return \count($this->nodes);
|
|
}
|
|
|
|
/**
|
|
* Get size of the graph.
|
|
*
|
|
* The size of the graph is the amount of edges it contains.
|
|
*
|
|
* @return int
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getSize() : int
|
|
{
|
|
$edges = $this->getEdges();
|
|
|
|
return \count($edges);
|
|
}
|
|
|
|
/**
|
|
* Get diameter of graph.
|
|
*
|
|
* The diameter of a graph is the longest shortest path between two nodes.
|
|
*
|
|
* @return int
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getDiameter() : int
|
|
{
|
|
$diameter = 0;
|
|
|
|
foreach ($this->nodes as $node1) {
|
|
foreach ($this->nodes as $node2) {
|
|
if ($node1 === $node2) {
|
|
continue;
|
|
}
|
|
|
|
/** @var int $diameter */
|
|
$diameter = \max($diameter, $this->getFloydWarshallShortestPath());
|
|
}
|
|
}
|
|
|
|
/** @var int $diameter */
|
|
return $diameter;
|
|
}
|
|
|
|
/**
|
|
* Get the graph girth
|
|
*
|
|
* @return int
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getGirth() : int
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Get the graph circuit rank
|
|
*
|
|
* @return int
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getCircuitRank() : int
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Get the graph node connectivity
|
|
*
|
|
* @return int
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getNodeConnectivity() : int
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Get the graph edge connectivity
|
|
*
|
|
* @return int
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function getEdgeConnectivity() : int
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* Is the graph connected?
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function isConnected() : bool
|
|
{
|
|
if (empty($this->nodes)) {
|
|
return true;
|
|
}
|
|
|
|
$nodes = $this->findAllReachableNodesDFS(\reset($this->nodes));
|
|
|
|
return \count($nodes) === \count($this->nodes);
|
|
}
|
|
|
|
/**
|
|
* Is the graph bipartite?
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function isBipartite() : bool
|
|
{
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Is the graph triangle?
|
|
*
|
|
* @return bool
|
|
*
|
|
* @since 1.0.0
|
|
*/
|
|
public function isTriangleFree() : bool
|
|
{
|
|
return true;
|
|
}
|
|
}
|