Deck 9: Advanced Array Concepts

Question 1

When mathematicians use a two-dimensional array, they often call it a ____.

A) grid
B) net
C) matrix
D) mesh

Answer 1

C

Question 2

In a(n) ____, you continue to compare pairs of items, swapping them if they are out of order, so that the smallest items rise to the top of the list, eventually creating a sorted list.

A) range match
B) bubble sort
C) enhanced for loop
D) float sort

Answer 2

B

Question 3

Since the Arrays class is part of the java.util package, you can use the java.util.*; import statement to access it.

Answer 3

True

Question 4

If you do not provide values for the elements in a two-dimensional numeric array, the values default to null.

Question 5

The Arrays class ____ method searches the specified array for the specified key value using the binary search algorithm.

A) binarySearch
B) sort
C) equals
D) search

Question 6

When using the Arrays.binarySearch() method, it is not necessary for the list to be in order because the binarySearch() method will sort the items when called.

Question 7

With a two-dimensional array, the ____ field holds the number of rows in the array.

A) size
B) capacity
C) row
D) length

Question 8

When working with two-dimensional arrays, the length field holds the number of rows in an array and each row has a length field that holds the number of columns in the row.

Question 9

The Arrays class ____ method returns true if the two specified arrays of the same type are equal to one another.

A) compare
B) sort
C) equals
D) fill

Question 10

____ is the process of arranging a series of objects in some logical order.

A) Passing
B) Organizing
C) Sorting
D) Sending

Question 11

You can think of the single dimension of a single dimensional array as the height of the array.

Question 12

How would you create an array named someNumbers that holds three rows and four columns?

A) int[][] someNumbers = new int[4][3]
B) int[][] someNumbers = new int[3][4]
C) int[] someNumbers = new int[3][4]
D) double[][] someNumbers = new int[3][4]

Question 13

To declare a two-dimensional array in Java, you type two sets of ____ after the array type.

A) { }
B) [ ]
C) ( )
D) < >

Question 14

When you pass a two-dimensional array to a method, you pass the array name just as you do with a one-dimensional array.

Question 15

The simplest possible sort involves two values that are out of order.

Question 16

An array that you can picture as a column of values, and whose elements you can access using one subscript, is a ____ array.

A) single-dimensional
B) two-dimensional
C) parallel
D) column

Question 17

The bubble sort is the fastest and most efficient sorting technique.

Question 18

When creating arrays, Java is limited in size due to limitations on the number of variables and subscripts used.

Question 19

When using an insertion sort, each list element is examined one at a time and moved down if the tested element should be inserted before them.

Question 20

Java provides a(n) ____ class, which contains many useful methods for manipulating arrays.

A) Object
B) Arrays
C) Table
D) Sort

Question 21

The Arrays class ____________________ method assigns the specified value to each element of the specified array.

Question 22

Regarding enumerations, the ____ method returns an integer that represents the constant's position in the list of constants; as with arrays, the first position is 0.

A) valueAt
B) positionOf
C) ordinal
D) indexOf

Question 23

The Arrays class ____________________ method sorts the specified array into ascending order.

Question 24

The negative integer returned by the binarySearch() method when the value is not found is the negative equivalent of the array ____.

A) type
B) scope
C) size
D) length

Question 25

int[] myVals = {2, 4, 6, 8} Using the above four-element array, what is the value of myVals[1]?

A) 2
B) 4
C) 6
D) 8

Question 26

int[][] myVals = {{2, 4, 6}, {1, 8, 9},
{1, 3, 5, 7}};
Using the above array, what is the value of myVals[1].length?

A) 1
B) 7
C) 3
D) 6

Question 27

A method that receives a two-dimensional array uses two ____________________ pairs following the data type in the parameter list of the method header.

Question 28

When you place objects in order beginning with the object that has the lowest value, you are sorting in ____________________ order.

Question 29

The ArrayList class ____ method retrieves an item from a specified location in an ArrayList.

A) extract
B) get
C) peek
D) retrieve

Question 30

double[][] empSales = new double[5][]; The above statement declares a(n) ____ array.

A) insertion
B) sort
C) ragged
D) boolean

Question 31

An ArrayList's ____ is the number of items it can hold without having to increase its size.

A) length
B) buffer
C) capacity
D) size

Question 32

The ArrayList class ____ method returns the current ArrayList size.

A) size
B) capacity
C) length
D) rows

Question 33

Programmers often refer to a ____ search as a "divide and conquer" procedure.

A) bubble
B) binary
C) division
D) split

Question 34

When you start with the object that has the largest value, you are sorting in ____________________ order.

Question 35

In Java, you create an enumerated data type in a statement that uses the keyword ____.

A) new
B) sequence
C) collection
D) enum

Question 36

int[][] myVals = {{2, 4, 6}, {1, 3, 5, 7}};
Using the above array, what is the value of myVals.length?

A) 1
B) 2
C) 4
D) 5

Question 37

The ArrayList class ____ method removes an item from an ArrayList at a specified location.

A) delete
B) get
C) erase
D) remove

Question 38

You can add an item at any point in a(n) ____ container and the array size expands automatically to accommodate the new item.

A) ArrayList
B) Array
C) ResizableArray
D) array

Question 39

Regarding enumerations, the ____ method returns the name of the calling constant object.

A) toString
B) constName
C) ordinal
D) nameOf

Question 40

Regarding enumerations, the ____ method returns an array of the enumerated constants.

A) valueOf
B) values
C) ordinal
D) toArray

Question 41

What are some of the advantages of declaring an ArrayList with a specified type?

Question 42

What are some of the advantages of creating an enumeration type?

Question 43

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
Use them with the class name without instantiating an object

Question 44

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
A popularly known sorting method

Question 45

Describe how to visualize the following array. How would you identify the location of the 99 that is stored in the array?
int[][] someNumbers = {{8, 9, 10, 11},
{1, 3, 12, 15},
{5, 9, 44, 99} };

Question 46

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
A two-dimensional array that has rows of different lengths

Question 47

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
Two or more columns of values

Question 48

How can you use the length field with a two-dimensional array?

Question 49

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
Adds an item to the end of an ArrayList

Question 50

What are some of the advantages of the ArrayList class over the Arrays class?

Question 51

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
Alters an item at a specified ArrayList location

Question 52

How can you sort arrays of objects?

Question 53

How can you pass a two-dimensional array to a method?

Question 54

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
A programmer-created data type with a fixed set of values

Question 55

Write the statement that assigns the integer value 20 to the first column of the first row of an array named myVals.

Question 56

Write the code for bubble sorting a someNums array of integers.

Question 57

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
Arrays with more than one dimension; allowed in Java

Question 58

What are the limitations of the ArrayList class?

Question 59

Match each term with the correct statement below.
a.ragged array
f.Enumerated data type
b.bubble sort
g.set() method
c.static methods
h.multidimensional array
d.two-dimensional array
i.java.util
e.add() method
A package containing the Arrays class

Question 60

What is sorting and how are objects organized as a result of being sorted?

Question 61

Write the statement to declare a three-by-four array of integers with the elements initialized to zero. Name the array myArray.

Question 62

int[][] myVals = {{10, 15, 20, 25},
{30, 35, 40, 45, 50, 55, 60},
{65, 70, 75, 80, 85, 90}};
Using the above array, what is the value of myVals.length? What is the value of myVals[1].length? What is the value of myVals[2].length? Explain how you determined these values.

Question 63

import javax.swing.*;
class FindPoints
{
public static void main(String[] args)
{
int[][] points = {{ 10, 20, 30},
{20, 40, 60},
{40, 60, 80}};
String prompt;
int class;
int level;
prompt = JOptionPane.showInputDialog(null, "Class: ");
class = Integer.parseInt(prompt);
prompt = JOptionPane.showInputDialog(null,

Question 64

int[][] studentScores = {{70, 82, 90, 68},
{95, 75, 67, 89},
{98, 79, 57, 81}};
Using the above two-dimensional array, what is the value of studentScores[0][0]? What is the value of studentScores[2][3]? What is the value of studentScores[1][2]? Describe how arrays reference values with subscripts.

Question 65

Dummy values are a common programming technique used with arrays. Explain the importance of dummy values and how they can be used to ensure that the subscript does not exceed the allowable limit.

Question 66

Write the statement to declare an ArrayList named myVals with a capacity of 15 items. Explain the importance of capacity when working with an ArrayList.

Question 67

enum Color {RED, GREEN, BLUE}
public class EnumOrdinal
{
public static void main(String[] args)
{
____
____
____
}
}
The above code demonstrates the use of the enum ordinal() method to get the ordinal value of an enum constant. Fill in the shaded lines with println() statements that will get the ordinal of the enumeration constant. Describe the output that will display when the code is executed.

Question 68

import javax.swing.*;
class FindPoints
{
public static void main(String[] args)
{
int[][] points = {{ 10, 20, 30},
{20, 40, 60},
{40, 60, 80}};
String prompt;
int class;
int level;
prompt = JOptionPane.showInputDialog(null, "Class: ");
class = Integer.parseInt(prompt);
prompt = JOptionPane.showInputDialog(null,

Question 69

int[][] myVals = new int[3][]
myVals[0] = new int[3];
myVals[1] = new int[10];
myVals[2] = new int[5];
The above code depicts a ragged array. What does this mean? Describe the rows and columns that make up this array.

Question 70

import java.util.*;
public class myArray
{
public static void main(String[] args)
{
int myVals = new int[4];
____
display("My values are: ", myVals);
}
public static void display(String message, int array[])
{
int arraySize = array.length;
System.out.print(message);
for(int x = 0; x < arraySize; ++x)
System.out.print(array[x] + " ");
}
}
Using the above code, complete the shaded section with a fill method() to fill each array element with a value of 2. What will be displayed after the display() method is executed?

Question 71

Using the ArrayList add() method, write the statement to insert "July" in the first position of the months ArrayList. Describe what would happen if the position number is invalid for the ArrayList.

Question 72

public class EnumExample
{
enum Day {SUNDAY, MONDAY, TUESDAY, WEDNESDAY,
THURSDAY, FRIDAY, SATURDAY };
Day day;
public EnumExample(Day day)
{
this.day = day;
}
public void giveFeedback()
{
switch (day)
{
case MONDAY:
System.out.println("Mondays are bad.");
break;
case FRIDAY:
System.out.println("Fridays are better.");
break;
case SATURDAY: case SUNDAY:
System.out.println("Weekends are best.");
break;
default:
System.out.println("Midweek days are so-so.");
break;
}
}
public static void main(String[] args)
{
EnumExample firstDay = new EnumExample(Day.MONDAY);
firstDay.giveFeedback();
EnumExample thirdDay = new EnumExample(Day.WEDNESDAY);
thirdDay.giveFeedback();
EnumExample fifthDay = new EnumExample(Day.FRIDAY);
fifthDay.giveFeedback();
EnumExample sixthDay = new EnumExample(Day.SATURDAY);
sixthDay.giveFeedback();
EnumExample seventhDay = new EnumExample(Day.SUNDAY);
seventhDay.giveFeedback();
}
}
Using the above enumeration and code, what will be the output when the program is executed?

Question 73

import java.util.*;
public class sortArray
{
public static void main(String[] args)
{
double[] lengths = {120.0, 0.5, 0.0, 999.0, 77.3};
Arrays.sort(lengths);
System.out.println(Arrays.toString(lengths));
}
}
Using the above code, what will be the output of the println statement when the code is executed?

Question 74

import java.util.*;
import javax.swing.*;
public class binary_search
{
public static void main(String[] args)
{
int myNums[]={2, 44, 5, 66, 78, 90, 23, 66};
int point, find = 78;
point = Arrays.binarySearch(myNums, find);
System.out.println("Element found at index " + point);
}
}
Using the above code, what output will be displayed when the program is executed? Describe how the binarySearch() method functions.