public boolean isValidCell(int row,int column, Grid grid) {
		if (row < 0 || row >= grid.getNumRows()) return false;
		else if (column < 0 || column >= grid.getNumColumns()) return false;
		GridCell cell = grid.getCellAt(row, column);
		if (cell.isSearched() && !canFlyOver) return false;
		else if (cell.isOccupied()) return false;
		else return true;
	}