public static Graph<int> DijkstrasAlg(Graph<int> graph)
{
List<Node<int>> nodeset = graph.nodeset.ToList<Node<int>>();
Graph<int> sptGraph = new Graph<int>();
while (nodeset.Count > 0)
{
Minheapify(nodeset);
Node<int> root = nodeset[0];
nodeset.RemoveAt(0);
Node<int> sptNode = new Node<int>(root.data);
if (root.parent != null)
{
sptGraph.AddEdge(sptNode, root.parent, root.key);
root.parent = null;
}
for (int i = 0; i < root.neighbors.Count; i++)
{
if (root.neighbors[i].key > (root.cost[i] + root.key))
{
root.neighbors[i].key = root.cost[i] + root.key;
root.neighbors[i].parent = sptNode;
}
}
}
sptGraph.printGraph();
return sptGraph;
}
static void Main(string[] args)
{
var n01 = new Node("01");
var n02 = new Node("02");
var n03 = new Node("03");
var n04 = new Node("04");
var n05 = new Node("05");
var n06 = new Node("06");
var n07 = new Node("07");
var n08 = new Node("08");
var n09 = new Node("09");
var n10 = new Node("10");
var n11 = new Node("11");
var n12 = new Node("12");
var n13 = new Node("13");
var n14 = new Node("14");
var n15 = new Node("15");
n01.AddChildren(n02).AddChildren(n03);
n02.AddChildren(n05);
n03.AddChildren(n04);
n04.AddChildren(n05, false).AddChildren(n10, false).AddChildren(n11, false);
n06.AddChildren(n01, false);
n07.AddChildren(n03, false).AddChildren(n08);
n09.AddChildren(n08).AddChildren(n10);
n11.AddChildren(n12).AddChildren(n13);
n12.AddChildren(n13);
n14.AddChildren(n15);
var search = new DepthFirstSearch();
var path = search.DLS(n06, n13,6);
PrintPath(path);
}
//Time: O(E logV) using adjacency list rep (using BFS on keys)
//Find minimum spanning tree (connected nodes with min cost edges, E = V-1)
//1. Place the graph in min heap (using keys)
//2. Extract the min key node and add to MST graph
//3. Update the keys of adjacent nodes (if key > cost then update)
//4. Minheapify the remaining nodes in the graph and repeat from step 2 until the entire list is empty
private static Graph<int> PrimsAlg(Graph<int> graph)
{
Graph<int> mstGraph = new Graph<int>(); //Generate a new MST graph
List<Node<int>> nodeset = graph.nodeset.ToList<Node<int>>(); //Create a new list of nodes from existing graph, so that we don't modify the given graph
while (nodeset.Count > 0)
{
Minheapify(nodeset); //Place the list in MinHeap
Node<int> root = nodeset[0]; //Extract Min node
Node<int> mstNode = new Node<int>(root.data); //Create a new node for MST graph
if (root.parent != null) //Add nodes and edges between them
{
mstGraph.AddEdge(mstNode, root.parent, root.key);
root.parent = null; //reset the parent node
}
nodeset.RemoveAt(0); //Extract root node (remove from list)
for(int i = 0; i< root.neighbors.Count; i++)
{
if (root.neighbors[i].key > root.cost[i]) //Update keys of neighboring nodes if the min node
{
root.neighbors[i].key = root.cost[i];
root.neighbors[i].parent = mstNode;
}
}
}
mstGraph.printGraph();
return mstGraph;
}
public Node AddChildren(Node node, bool bidirect = true)
{
Children.Add(node);
if (bidirect)
{
node.Children.Add(this);
}
return this;
}
public LinkedList<Node> IDDFS(Node start, Node goal)
{
for (int limit = 1; ; limit++)
{
var result = DLS(start, goal, limit);
if (result.Count > 0 || limitWasReached)
{
return result;
}
}
}
public LinkedList<Node> DFS(Node start, Node goal)
{
visited = new HashSet<Node>();
path = new LinkedList<Node>();
this.goal = goal;
DFS(start);
if (path.Count > 0)
{
path.AddFirst(start);
}
return path;
}
public LinkedList<Node> DLS(Node start, Node goal, int limit)
{
visited = new HashSet<Node>();
path = new LinkedList<Node>();
limitWasReached = true;
this.goal = goal;
DLS(start, limit);
if (path.Count > 0)
{
path.AddFirst(start);
}
return path;
}
public void ConnectNode(Node start, Node end)
{
if (_adjMatrix == null)
{
_size = _nodes.Count;
_adjMatrix = new int[_size, _size];
}
int startIndex = _nodes.IndexOf(start);
int endIndex = _nodes.IndexOf(end);
_adjMatrix[startIndex, endIndex] = 1;
_adjMatrix[endIndex, startIndex] = 1;
}
private bool DFS(Node node)
{
node.Handler();
if (node == goal)
{
return true;
}
visited.Add(node);
foreach (var child in node.Children.Where(x => !visited.Contains(x)))
{
if (DFS(child))
{
path.AddFirst(child);
return true;
}
}
return false;
}
private bool DLS(Node node, int limit)
{
node.Handler();
if (node == goal)
{
return true;
}
if (limit == 0)
{
limitWasReached = false;
return false;
}
visited.Add(node);
foreach (var child in node.Children.Where(x => !visited.Contains(x)))
{
if (DLS(child, limit - 1))
{
path.AddFirst(child);
return true;
}
}
return false;
}
public Graph(Edge[] edges, Node[] nodes)
{
this.edges = edges;
this.nodes = nodes;
}
public override void ForEach(Action <StackSourceSample> callback)
{
// Initialize the priority
if (m_typePriorities == null)
{
PriorityRegExs = DefaultPriorities;
}
Debug.Assert(m_typePriorities != null);
// Initialize the breadth-first work queue.
var nodesToVisit = new PriorityQueue(1024);
nodesToVisit.Enqueue(m_graph.RootIndex, 0.0F);
// reset the visited information.
for (int i = 0; i < m_parent.Length; i++)
{
m_parent[i] = NodeIndex.Invalid;
}
// We keep track of node depth so that we can limit it.
int[] nodeDepth = new int[m_parent.Length];
float[] nodePriorities = new float[m_parent.Length];
MemoryGraph asMemoryGraph = m_graph as MemoryGraph;
bool scanedForOrphans = false;
var epsilon = 1E-7F; // Something that is big enough not to bet lost in roundoff error.
float order = 0;
for (int i = 0; ; i++)
{
if ((i & 0x1FFF) == 0) // Every 8K
{
System.Threading.Thread.Sleep(0); // Allow interruption.
}
NodeIndex nodeIndex;
float nodePriority;
if (nodesToVisit.Count == 0)
{
nodePriority = 0;
if (!scanedForOrphans)
{
scanedForOrphans = true;
AddOrphansToQueue(nodesToVisit);
}
if (nodesToVisit.Count == 0)
{
return;
}
}
nodeIndex = nodesToVisit.Dequeue(out nodePriority);
// Insert any children that have not already been visited (had a parent assigned) into the work queue).
Node node = m_graph.GetNode(nodeIndex, m_nodeStorage);
var parentPriority = nodePriorities[(int)node.Index];
for (var childIndex = node.GetFirstChildIndex(); childIndex != NodeIndex.Invalid; childIndex = node.GetNextChildIndex())
{
if (m_parent[(int)childIndex] == NodeIndex.Invalid && childIndex != m_graph.RootIndex)
{
m_parent[(int)childIndex] = nodeIndex;
int parentDepth = nodeDepth[(int)nodeIndex];
nodeDepth[(int)childIndex] = checked (parentDepth + 1);
// the priority of the child is determined by its type and 1/10 by its parent.
var child = m_graph.GetNode(childIndex, m_childStorage);
var childPriority = m_typePriorities[(int)child.TypeIndex] + parentPriority / 10;
nodePriorities[(int)childIndex] = childPriority;
// Subtract a small increasing value to keep the queue in order if the priorities are the same.
// This is a bit of a hack since it can get big and perturb the user-defined order.
order += epsilon;
nodesToVisit.Enqueue(childIndex, childPriority - order);
}
}
// Return the node.
m_sampleStorage.Metric = node.Size;
// We use the address as the timestamp. This allows you to pick particular instances
// and see where particular instances are in memory by looking at the 'time'.
if (asMemoryGraph != null)
{
m_sampleStorage.TimeRelativeMSec = asMemoryGraph.GetAddress(node.Index);
}
m_sampleStorage.SampleIndex = (StackSourceSampleIndex)node.Index;
m_sampleStorage.StackIndex = (StackSourceCallStackIndex)node.Index;
if (m_countMultipliers != null)
{
m_sampleStorage.Count = m_countMultipliers[(int)node.TypeIndex];
m_sampleStorage.Metric = node.Size * m_sampleStorage.Count;
}
Debug.Assert(m_sampleStorage.Metric >= 0);
Debug.Assert(m_sampleStorage.Count >= 0);
Debug.Assert(0 < m_sampleStorage.Count && m_sampleStorage.Count <= float.MaxValue);
Debug.Assert(0 <= m_sampleStorage.Metric && m_sampleStorage.Metric <= float.MaxValue);
callback(m_sampleStorage);
}
}
/// <summary>
/// Gives back nodes that are no longer in use. This is a memory optimization.
/// </summary>
private void FreeNodeStorage(Node node)
{
m_cachedNodeStorage = node;
}
public Edge(int w, Node u, Node v)
{
this.weight = w;
this.u = u;
this.v = v;
}
public void SetRootNode(Node n)
{
this._rootNode = n;
}
public void AddNode(Node n)
{
_nodes.Add(n);
}
private Node GetUnvisitedChildNode(Node n)
{
int index = _nodes.IndexOf(n);
int j = 0;
while (j < _size)
{
if (_adjMatrix[index, j] == 1 && _nodes[j].visited == false)
{
return _nodes[j];
}
j++;
}
return null;
}
