public boolean isSuicideMove(int sx, int sy, int tx, int ty) {
		if (board[tx][ty] != EMPTY_FIELD)
			return true;
		if (sx != moveLeft(tx) && board[moveLeft(tx)][ty] == EMPTY_FIELD)
			return false;
		if (sx != moveRight(tx) && board[moveRight(tx)][ty] == EMPTY_FIELD)
			return false;
		if (sy != moveUp(ty) && board[tx][moveUp(ty)] == EMPTY_FIELD)
			return false;
		if (sy != moveDown(ty) && board[tx][moveDown(ty)] == EMPTY_FIELD)
			return false;
		return true;
	}