private int AlphaBeta(Tree.Node node, int maxDepth, int currDepth, int alpha, int beta)
{
if (node.State.HeuristicFunction() == 0)
{
if (currDepth % 2 == 0)
{
return(node.Value = 0);
}
else
{
return(node.Value = 1);
}
}
if (currDepth == maxDepth)
{
if (currDepth % 2 == 0)
{
return(node.Value = 1);
}
else
{
return(node.Value = 0);
}
}
int bestValue, currValue;
if (currDepth % 2 == 0)
{
bestValue = Int32.MinValue;
}
else
{
bestValue = Int32.MaxValue;
}
for (int j = 0; j < node.Children.Count; j++)
{
currValue = AlphaBeta(node.Children[j], maxDepth, currDepth + 1, alpha, beta);
if (currDepth % 2 == 0 && currValue > bestValue)
{
bestValue = currValue;
if (bestValue >= beta)
{
j = node.Children.Count;
return(node.Value = bestValue);
}
alpha = Math.Max(alpha, bestValue);
}
if (currDepth % 2 == 1 && currValue < bestValue)
{
bestValue = currValue;
if (bestValue <= alpha)
{
return(node.Value = bestValue);
}
beta = Math.Min(beta, bestValue);
}
}
return(node.Value = bestValue);
}
private int move(Tree.Node node, int maxDepth, int currDepth)
{
if (node.State.HeuristicFunction() == 0)
{
if (currDepth % 2 == 0)
{
return(node.Value = 0);
}
else
{
return(node.Value = 1);
}
}
if (currDepth == maxDepth)
{
if (currDepth % 2 == 0)
{
return(node.Value = 1);
}
else
{
return(node.Value = 0);
}
}
int bestValue, currValue;
if (currDepth % 2 == 0)
{
bestValue = Int32.MinValue;
}
else
{
bestValue = Int32.MaxValue;
}
for (int j = 0; j < node.Children.Count; j++)
{
currValue = move(node.Children[j], maxDepth, currDepth + 1);
if (currDepth % 2 == 0 && currValue > bestValue)
{
bestValue = currValue;
}
if (currDepth % 2 == 1 && currValue < bestValue)
{
bestValue = currValue;
}
}
return(node.Value = bestValue);
}