public bool Equals(Node other)
{
if (c != other.c)
return false;
if (position.Length != other.position.Length)
return false;
for (int i = 0; i < position.Length; ++i)
if (!position[i].Equals(other.position[i]))
return false;
return true;
}
public Node MostProving(Node v)
{
Node.InitiateVisiting ();
while (v.children != null) {
v = LeftmostNode (v);
if (v.IsVisited ()) {
//v.pn *= 2;
//v.dn *= 2;
break;
}
}
return v;
}
public Node LeftmostNode(Node v)
{
v.SetVisit ();
foreach (var child in v.children)
if (v.c == 1) {
if (child.pn == v.pn && !child.IsVisited ())
return child;
} else {
if (child.dn == v.dn && !child.IsVisited ())
return child;
}
return v;
}
public void UpdateTree(Node n, bool firstRun)
{
if (this.Equals (n)) {
if (firstRun)
{
n.pn = Int32.MaxValue;
n.dn = 0;
}
else
{
n.pn = 0;
n.dn = Int32.MaxValue;
}
n.Update ();
return;
}
UpdateNumbers();
foreach(var parent in parents)
parent.UpdateTree(n, firstRun);
}
public void ExpandTree(Game g, ref int nodeCount, ref int collisionCount, Hashtable transposition)
{
if(children != null)
return;
children = new List<Node>();
var plies = g.children(position, c);
foreach (var ply in plies)
{
var s = new Node(ply.Apply(position, g), (byte)(c ^ 1));
s.Evaluate(g);
nodeCount++;
if (transposition.ContainsKey(s))
collisionCount++;
else
transposition.Add(s, s);
s.parents.Add(this);
children.Add(s);
}
}
public void Expand(Game g, Hashtable transposition)
{
if(children != null)
return;
children = new List<Node>();
var plies = g.children(position, c);
foreach (var ply in plies)
{
var s = new Node(ply.Apply(position, g), (byte)(c ^ 1));
if (transposition.ContainsKey(s))
s = (Node)transposition[s];
else
{
s.Evaluate(g);
transposition[s] = s;
}
s.parents.Add(this);
children.Add(s);
}
}
public void Prove(Game g)
{
root = new Node (g.startingPos, 1);
root.Evaluate (g);
transposition [root] = root;
nodeCount++;
Node lastExpanded = null;
int lastpn = 0, lastdn = 0;
int count = 0;
Stopwatch sw = new Stopwatch ();
sw.Start ();
while (root.pn != 0 && root.dn != 0) {
var mpn = MostProving (root);
if (graph) {
if (System.Object.ReferenceEquals (mpn, lastExpanded) && lastpn == mpn.pn && lastdn == mpn.dn) {
sw.Stop ();
timeSpent = (int)sw.ElapsedMilliseconds;
throw new Exception ("Loop in finding most proving");
}
mpn.Expand (g, transposition);
mpn.StartUpdate ();
lastExpanded = mpn;
lastpn = mpn.pn;
lastdn = mpn.dn;
} else {
mpn.ExpandTree (g, ref nodeCount, ref collisionCount, transposition);
mpn.StartUpdateTree (firstRun);
if (count % 10000 == 0)
{
Console.WriteLine("PN: {0}\nDN: {1}", root.pn, root.dn);
Console.WriteLine("Collisions: " + collisionCount);
Console.WriteLine("Nodes: " + nodeCount);
}
count++;
}
if (sw.ElapsedMilliseconds > timeLimit * 60000) {
sw.Stop ();
timeSpent = (int)sw.ElapsedMilliseconds;
throw new Exception ("Time limit exceeded");
}
}
sw.Stop ();
timeSpent = (int)sw.ElapsedMilliseconds;
// If this is the first run of a graph search where black loses, run again to check for draw
if (!graph && firstRun && root.dn == 0) {
second = new PNSearch (false, timeLimit);
second.firstRun = false;
second.Prove (g);
}
}