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Assume you are using a doubly-linked list data structure with many nodes. What is the minimum number of node references that are required to be modified to remove a node from the middle of the list? Consider the neighboring nodes.

Consider the following class hierarchy: public class Vehicle { private String type; public Vehicle(String type) { this.type = type; } public String displayInfo() { return type; } } public class LandVehicle extends Vehicle { public LandVehicle(String type) { super(type); } } public class Auto extends LandVehicle { public Auto(String type) { super(type); } } You have written a program to use these classes, as shown in the following code snippet: public class VehicleTester { public static void main(String[] args) { Auto myAuto = new Auto(“sedan”); System.out.println(“MyAuto type = ” + ______); } } Complete the code in this program snippet to correctly display the auto’s type.

Select an appropriate expression to complete the following method, which is designed to return the number of elements in the parameter array numbers.  If a value appears more than once, it should be counted exactly once. public static int countElementsOnce(int[] numbers) { Set values = new HashSet(); for (int num: numbers) { values.add(num); } ______________________ }

Consider the following class hierarchy: public class Vehicle { private String type; public Vehicle(String type) { this.type = type; } public String displayInfo() { return type; } } public class LandVehicle extends Vehicle { public LandVehicle(String type) { super(type); } } public class Auto extends LandVehicle { public Auto(String type) { super(type); } } You have written a program to use these classes, as shown in the following code snippet: public class VehicleTester { public static void main(String[] args) { Auto myAuto = new Auto(“sedan”); System.out.println(“MyAuto type = ” + ______); } } Complete the code in this program snippet to correctly display the auto’s type.

Suppose the class Value is partially defined below public class Value { private int number; public int getValue() { return number; } } A subclass of Value, LargerValue, is defined with a getValue method that returns twice the value of the parent.  Which line is the body of LargerValue’s getValue method?

Consider the following code snippet. String line = …; Scanner lineScanner = new Scanner(line); Which of the following statements about this code is correct?

Select an appropriate expression to complete the following method, which is designed to return the number of elements in the parameter array numbers.  If a value appears more than once, it should be counted exactly once. public static int countElementsOnce(int[] numbers) { Set values = new HashSet(); for (int num: numbers) { values.add(num); } ______________________ }

Consider the following code snippet: public class Motorcycle extends Vehicle { . . . public Motorcycle(int numberAxles) { super.numberAxles = numberAxles; } } What does this code do?

Assume inputFile is a Scanner object used to read data from a text file that contains a number of lines.  Some lines contain an alphabetic string, while others contain a single integer value.  Select an expression to complete the following code segment, which counts the number of integer values in the input file. int count = 0; while (inputFile.hasNextLine()) { if (________________________________) { count++; } inputFile.nextLine(); } System.out.println(count);

The ______ method of the Scanner class specifies a pattern for word boundaries when reading text.