public object Result(object s, IAction a)
{
if (a is QueenAction)
{
QueenAction qa = (QueenAction)a;
NQueensBoard board = (NQueensBoard)s;
NQueensBoard newBoard = new NQueensBoard(board.Size);
newBoard.SetBoard(board.GetQueenPositions());
if (qa.GetName() == QueenAction.PlaceQueen)
{
newBoard.AddQueenAt(qa.GetLocation());
}
else if (qa.GetName() == QueenAction.RemoveQueen)
{
newBoard.RemoveQueenFrom(qa.GetLocation());
}
else if (qa.GetName() == QueenAction.MoveQueen)
{
newBoard.MoveQueenTo(qa.GetLocation());
}
s = newBoard;
}
// if action is not understood or is a NoOp
// the result will be the current state.
return(s);
}
public bool Equals(NQueensBoard other)
{
if (ReferenceEquals(null, other))
{
return(false);
}
if (ReferenceEquals(this, other))
{
return(true);
}
return(Equals(other.squares, this.squares) && other.Size == this.Size);
}
public NQueensBoard GetBoardForIndividual(string individual)
{
var boardSize = individual.Length;
var board = new NQueensBoard(boardSize);
for (var i = 0; i < boardSize; i++)
{
var pos = Int32.Parse(individual.Substring(i, 1));
if (pos > boardSize)
{
pos = -1;
}
board.AddQueenAt(new XYLocation(i, pos));
}
return(board);
}
public ISet <IAction> Actions(object state)
{
NQueensBoard board = (NQueensBoard)state;
ISet <IAction> actions = new HashedSet <IAction>();
var numQueens = board.GetNumberOfQueensOnBoard();
var boardSize = board.Size;
for (var i = 0; i < boardSize; i++)
{
var newLocation = new XYLocation(numQueens, i);
if (!(board.IsSquareUnderAttack(newLocation)))
{
actions.Add(new QueenAction(QueenAction.PlaceQueen,
newLocation));
}
}
return(actions);
}
public double H(object state)
{
NQueensBoard board = (NQueensBoard)state;
return(board.GetNumberOfAttackingPairs());
}