public NodeIterator(Node start, int n) {
for (int i = -2; i <= 2; i++) {
for (int j = -2; j <= 2; j++) {
Board settingClone = new BoardImpl((BoardImpl) setting);
Player moverClone = new PlayerImpl(owner);
settingClone.getPawn(moverClone, settingClone).setSquare(square);
MovePawn tentative =
new MovePawnImpl(
square.getCol() + j, square.getRow() + i, moverClone, settingClone);
if (tentative.isValid()) {
nextList.add(
new Node(
new SquareImpl(square.getCol() + j, square.getRow() + i),
n + 1,
moverClone,
start));
}
}
}
backer = nextList.iterator();
}
public int pathLengthMin() {
Player player;
if (playerType(currentTurn) == MIN) {
player = currentTurn;
} else {
player = currentTurn.getOpponent();
}
if (bestMin == null) {
Queue<Node> toVisit = new LinkedList<Node>();
Node current = new Node(setting.getPawn(player, setting).getSquare(), 0, player, null);
toVisit.add(current);
HashSet<Node> seen = new HashSet<Node>();
while (current.getSquare().getRow() != destRow(player.goalEnd())) {
current = toVisit.remove();
seen.add(current);
for (Node n : current) {
if (!seen.contains(n)) {
toVisit.add(n);
}
}
}
bestMin = new LinkedList<Node>();
while (current != null) {
bestMin.add(current);
current = current.getParent();
}
}
return bestMin.size();
}
private void populate() {
// populate with MovePawns
for (int i = -2; i <= 2; i++) {
for (int j = -2; j <= 2; j++) {
Square tmp = setting.getPawn(mover, setting).getSquare();
Board settingClone = new BoardImpl((BoardImpl) setting);
Player moverClone = new PlayerImpl(mover);
MovePawn tentative =
new MovePawnImpl(tmp.getCol() + j, tmp.getRow() + i, moverClone, settingClone);
if (tentative.isValid()) {
pawnBackerList.add(new StateImpl(settingClone, moverClone, tentative));
}
}
}
for (int i = 0; i < 8; i++) {
for (int j = 0; j < 8; j++) {
Board settingClone = new BoardImpl((BoardImpl) setting);
Player moverClone = new PlayerImpl(mover);
PlaceWall vTentative = new PlaceWallImpl(i, j, Wall.VERTICAL, moverClone, settingClone);
settingClone = new BoardImpl((BoardImpl) setting);
moverClone = new PlayerImpl(mover);
PlaceWall hTentative = new PlaceWallImpl(i, j, Wall.HORIZONTAL, moverClone, settingClone);
if (vTentative.isValid()) {
wallBackerList.add(new StateImpl(settingClone, moverClone, vTentative));
}
if (hTentative.isValid()) {
wallBackerList.add(new StateImpl(settingClone, moverClone, hTentative));
}
}
}
}
public int alphabetaNum(int alpha, int beta, int depth) {
if (depth == 0
|| setting.getPawn(currentTurn, setting).getSquare().getRow()
== destRow(currentTurn.goalEnd())) {
determineScore();
return score;
}
int tmp;
Iterator<StateImpl> nextMoves = swapIterator();
StateImpl s = null;
if (playerType(currentTurn) == MIN) {
while (nextMoves.hasNext() && alpha < beta) {
s = nextMoves.next(); // get a new state
s.nextMove.makeMove(); // apply the current move
if (s.nextMove.type() == GenericMove.PAWN) {
bestMin = null;
} else {
clearBestMin(s.setting);
}
tmp = s.alphabetaNum(alpha, beta, depth - 1);
if (tmp > alpha) {
alpha = tmp;
}
if (alpha >= beta) {}
}
return alpha;
}
if (playerType(currentTurn) == MAX) {
while (nextMoves.hasNext() && alpha < beta) {
s = nextMoves.next(); // get a new state
s.nextMove.makeMove(); // apply the current move
if (s.nextMove.type() == GenericMove.PAWN) {
bestMax = null;
} else {
clearBestMax(s.setting);
}
tmp = s.alphabetaNum(alpha, beta, depth - 1);
if (tmp < beta) {
beta = tmp;
}
if (alpha >= beta) {}
}
return beta;
}
return 0;
}
