private int minValue(StateNode currentNode, int depth, int alpha, int beta)
{
if (currentNode.isTerminalNode())
{
currentNode.setAlpha(alpha);
currentNode.setBeta(beta);
StateNode.win_count++;
return(currentNode.getValue());
}
else
{
currentNode.setAlpha(alpha);
currentNode.setBeta(beta);
currentNode.setValue(1000);
foreach (StateNode child in currentNode.Children)
{
currentNode.setValue(Math.Min(currentNode.getValue(), maxValue(child, depth++, currentNode.getAlpha(), currentNode.getBeta())));
currentNode.setBeta(Math.Min(currentNode.getBeta(), currentNode.getValue()));
if (currentNode.getBeta() <= currentNode.getAlpha())
{
return(currentNode.getValue());
}
}
return(currentNode.getValue());
}
}
public StateTree(int m, int n)
{
int[,] initState = new int[m, n];
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
initState[i, j] = 0;
}
}
root = new StateNode(initState, null);
generateStates();
}
public StateNode(int[,] state, StateNode _Parent)
{
gridState = state;
Parent = _Parent;
if (Parent != null)
{
max_node = !Parent.getNodeType();
}
else
{
max_node = true;
}
Children = new LinkedList <StateNode>();
alpha = -1000;
beta = 1000;
}
public int[,] getBestState(StateNode currentNode)
{
alpha = -1000;
beta = 1000;
int depth = 0;
int nodeValue = maxValue(currentNode, depth, alpha, beta);
int[,] nodeState = CopyArray(root.getState());
foreach (StateNode child in currentNode.Children)
{
if (child.getValue() == nodeValue)
{
nodeState = CopyArray(child.getState());
break;
}
}
return(nodeState);
}
public void setNewRoot(int[,] newState)
{
int[,] state = CopyArray(newState);
root = new StateNode(state, null);
generateStates();
}
public void setRoot(StateNode current)
{
root = current;
generateStates();
}
private void generateStates()
{
int MAX = 1;
int MIN = 2;
int TURNVAL = 0;
bool MAXTURN = true;
int CONNECTBY = 4;
int M = 4;
int N = 4;
int MAXDEPTH = 9;//M * N;
int DEPTH = 1;
long count = 0;
Queue <StateNode> currentLevel = new Queue <StateNode>();
Queue <StateNode> nextLevel = new Queue <StateNode>();
StateNode currentNode;
currentLevel.Enqueue(root);
//While the depth of the tree is less than or equal to 8
//and the number of nodes at the current level of the tree
//is greater than 0
while (DEPTH <= MAXDEPTH && currentLevel.Count > 0)
{
if (MAXTURN)
{
TURNVAL = 1;
}
else
{
TURNVAL = 2;
}
//Switch turns in tree
MAXTURN = !MAXTURN;
//Probably not the best way to implement this, but
//this loop will deplete the currentLevel, and then
//repopulate it with the nodes from next level
while (currentLevel.Count > 0)
{
//Find a node that has children and while currentLevel has children
do
{
currentNode = currentLevel.Dequeue();
} while (currentNode.Children == null && currentLevel.Count > 0);
for (int i = 0; i < N; i++)
{
bool STATEFILLED = false;
int j = M - 1;
if (currentNode.gridState[0, i] == 0)
{
while (j >= 0 && !STATEFILLED)
{
if (currentNode.gridState[j, i] == 0)
{
int[,] newState;
StateNode newStateNode;
newState = CopyArray(currentNode.gridState);
newState[j, i] = TURNVAL;
newStateNode = new StateNode(newState, currentNode);
if (IsWinningTermState(newState, TURNVAL, CONNECTBY))
{
newStateNode.Children = null;
if (TURNVAL == MAX)
{
newStateNode.setValue(1 * DEPTH);
}
else
{
newStateNode.setValue(-1 * DEPTH);
}
}
else if (IsNonWinningTermState(newState, TURNVAL))
{
newStateNode.Children = null;
newStateNode.setValue(0);
}
/*if (DEPTH >= (2 * CONNECTBY - 1))
* {
* if (IsWinningTermState(newState, TURNVAL, CONNECTBY))
* {
* newStateNode.Children = null;
* if (TURNVAL == MAX)
* newStateNode.setValue(1);
* else
* newStateNode.setValue(-1);
*
* }
* else if( DEPTH == MAXDEPTH )
* {
* newStateNode.Children = null;
* newStateNode.setValue(0);
* }
* }*/
count++;
currentNode.Children.AddLast(newStateNode);
STATEFILLED = true;
}
j--;
}
}
}
foreach (StateNode n in currentNode.Children)
{
if (n.Children != null)
{
nextLevel.Enqueue(n);
}
}
}
while (nextLevel.Count > 0)
{
currentLevel.Enqueue(nextLevel.Dequeue());
}
DEPTH++;
}
}