/// <summary>
/// Collisions are handled by returning the existing node. Thread-safe
/// Does not recalculate height, do that after all positions are added.
/// </summary>
/// <param name="info">Connector in a tree structure</param>
/// <returns>Node the position was already store in, null if new node.</returns>
public MiniMax.Node AddConnection(MiniMax.Node chessNode)
{
if (this.info == null)
{
lock (this)
{
// Must check again, in case it was changed before lock.
if (this.info == null)
{
this.left = new BinaryTree();
this.right = new BinaryTree();
this.info = chessNode;
return(null);
}
}
}
int difference = this.info.position.CompareTo(chessNode.position);
if (difference < 0)
{
return(this.left.AddConnection(chessNode));
}
else if (difference > 0)
{
return(this.right.AddConnection(chessNode));
}
else
{
this.info.IncreaseReferenceCount();
return(this.info);
}
}
/// <summary>
/// Construct a new Binary search tree from an array.
/// </summary>
/// <param name="elements">Array of elements, inorder.</param>
/// <param name="min">First element of this branch.</param>
/// <param name="max">Last element of this branch.</param>
public void CreateFromArray(MiniMax.Node[] elements, int min, int max)
{
if (max >= min)
{
int mid = (min + max) >> 1;
this.info = elements[mid];
this.left = new BinaryTree();
this.right = new BinaryTree();
// The left and right each have one half of the array, exept the mid.
this.left.CreateFromArray(elements, min, mid - 1);
this.right.CreateFromArray(elements, mid + 1, max);
}
}
