Deck 6: Arrays

Question 1

Java provides a looping mechanism for objects of a collection.This looping mechanism is called a __________ loop.

A)While
B)For
C)For each
D)All of the above

Answer 1

C

Question 2

The correct syntax for accessing the length of an array named Numbers is:

A)Numbers.length)
B)Numbers.length
C)both A and B
D)none of the above

Answer 2

B

Question 3

An arrays length instance variables value can be changed by a program.

Answer 3

False

Question 4

Which of the following initializer lists correctly initializes the indexed variables of an array named myDoubles?

A)double myDoubles[double] = {0.0,1.0,1.5,2.0,2.5};
B)double myDoubles[5] = new double0.0,1.0,1.5,2.0,2.5);
C)double[] myDoubles = {0.0,1.0,1.5,2.0,2.5};
D)array myDoubles[double] = {0.0,1.0,1.5,2.0,2.5};

Question 5

An ArrayIndexOutOfBounds error is a:

A)compiler error
B)syntax error
C)logic error
D)all of the above

Question 6

A value of an enumerated type is similar to a/an:

A)Instance variable
B)Object of a class
C)Named constant
D)None of the above

Question 7

This type of loop provides a convenient mechanism to iterate through every element of an array.

A)for each
B)for
C)do while
D)while

Question 8

What is the correct expression for accessing the 5< sup >th< /sup > element in an array named colors?

A)colors[3]
B)colors[4]
C)colors[5]
D)colors[6]

Question 9

The name of the sorting algorithm that locates the smallest unsorted value in an array and places it in the next sorted position of the array is called:

A)bubble sort
B)merge sort
C)radix sort
D)selection sort

Question 10

Consider the following array: What is the value of myArray[myArray[1] - myArray[0]]

A)7
B)9
C)-3
D)6

Question 11

The base type of an array may be all of the following but:

A)string
B)boolean
C)long
D)all of these may be a base type of an array.

Question 12

The individual variables that together make up the array are referred to as:

A)indexed variables
B)subscripted variables
C)elements of the array
D)all of the above

Question 13

An array is a collection of variables all of the same type.

Question 14

A type of array in which different rows can have different number of columns is called a/an:

A)partially filled array
B)ragged array
C)initialized array
D)none of the above

Question 15

A ________ loop is a good way to step through the elements of an array and perform some program action on each indexed variable.

A)while
B)do…while
C)for
D)all of the above

Question 16

A _________ can occur if a programmer allows an accessor method to return a reference to an array instance variable.

A)short circuit
B)privacy leak
C)partially filled array
D)syntax error

Question 17

An array with more than one index is called a/an:

A)partially filled array
B)multidimensional array
C)bidirectional array
D)one dimensional array

Question 18

The subscript of the first indexed variable in an array is:

A)0
B)1
C)2
D)3

Question 19

Partially filled arrays require:

A)a variable to track the number of array positions used
B)the use of local variables
C)the use of global variables
D)all of the above

Question 20

An array has only one public instance variable,which is named length.

Question 21

A method can not change the values stored in the indexed variables of an array argument.

Question 22

Given the following character array
char[] h = {'H','E','L','L','O'};
Write a Java statement that will create a new String object from the character array.

Question 23

You may cycle through elements of a collection object using a for loop.

Question 24

Write a Java method that takes an integer array as a formal parameter and returns the sum of integers contained within the array.

Question 25

A variable of an enumerated type can have the special value null.

Question 26

Arrays are objects that are created with new just like class objects.

Question 27

What are three ways you can use the square brackets [ ] with an array name?

Question 28

Java allows you to declare arrays with more than one index.

Question 29

An array of chars is the same as a String in Java.

Question 30

How are arrays tested to see if they contain the same contents?

Question 31

Write a Java statement that declares and creates an array of Strings named Breeds.Your array should be large enough to hold the names of 100 dog breeds.

Question 32

Explain what the main methods array parameter,args,is used for.

Question 33

Declare and create an integer array that will contain the numbers 1 through 100.Use a for loop to initialize the indexed variables.

Question 34

You can only use array indexed variables as arguments to methods.

Question 35

A collection class is a class whose objects store a collection of values.

Question 36

A one dimensional array is also called an array of arrays.

Question 37

An array name references a memory address.

Question 38

In a vararg specification the ellipsis is not part of the Java syntax.

Question 39

Write a Java method as well as any facilitator methods needed to perform a sort on an array of whole numbers in descending order.

Question 40

Discuss how you could represent a table of related records using a multidimensional array.

Question 41

What is the output of the following code?
int[] numbers = new int[10];
forint i=0;i < numbers.length;++i)
numbers[i] = i * 2;
forint i=0;i < numbers.length;++i)
System.out.printnumbers[i] / 2 + " ");
System.out.println);

Question 42

Write a complete Java console application that prompts the user for a series of quiz scores.The user should type -1 to signify that the input of quiz scores is complete.Your program should then average the scores and display the result back to the user.

Question 43

Initialize the array created in number 11 above to -1.0.

Question 44

Declare and create a 10 x 10 multidimensional array of doubles.

Question 45

Declare and create a multidimensional array to hold the first and last names of 10 people.

Question 46

What is the output of the following code?
int[] numbers = new int[10];
forint i=0;i < numbers.length;++i)
numbers[i] = i * 2;
forint i=0;i < numbers.length;++i)
System.out.printnumbers[i] + " ");
System.out.println);