Deck 7: Arrays and Lists

Question 1

When you create a numeric array in C#, what value are its elements set to by default?

A) null
B) 0
C) 255
D) -1

Answer 1

B

Question 2

When you create an array, you can optionally initialize it with a group of values called a(n) ____________.

A) initialization list
B) default group
C) element assembly
D) starting run

Answer 2

A

Question 3

When you are working with a(n) ____________ variable, the compiler sets aside, or allocates, a chunk of memory that is big enough for that variable.

A) reference type
B) uninitialized
C) value type
D) dynamic type

Answer 3

C

Question 4

Which one of the following assignment statements associates an int array, that can hold 12 integers, with a reference variable named scores?

A) scores = new int[12];
B) int[12] = new scores;
C) int scores[12];
D) new int scores[12]

Question 5

What special value are the elements of an array of reference type objects set to by default?

A) 0
B) void
C) -1
D) null

Question 6

The storage locations in an array are known as ____________.

A) values
B) sectors
C) compartments
D) elements

Question 7

The ____________ creates an object in memory and returns a reference to that object.

A) .NET Framework
B) new operator
C) = operator
D) % operator

Question 8

Which one of the following statements is not a valid array declaration?

A) double[] parsecs = new double[10];
B) decimal[] sales = new decimal[24.5m];
C) string[] cities = new decimal[50];
D) int[] quarters = new int[4];

Question 9

It is preferred practice to use a(n) ____________ as an array's size declarator.

A) variable
B) literal value
C) named constant
D) object

Question 10

Of the following statements, which one correctly initializes an int array named quarters with the values 1, 2, 3, and 4?

A) const int SIZE = 4; int[] quarters = new int[SIZE] { 1, 2, 3, 4 };
B) int[] quarters = new int[] { 1, 2, 3, 4 };
C) int[] quarters = { 1, 2, 3, 4 };
D) All of these statements are correct.

Question 11

A(n) ____________ is an object that can hold a group of values that are all the same data type.

A) matrix
B) list
C) array
D) container

Question 12

An array's____________ indicates the number of values that the array should be able to hold.

A) reference variable
B) size declarator
C) element
D) subscript

Question 13

Which one of the following declaration statements is not a value type?

A) decimal grossPay = 0.0m;
B) int playerScore = 0;
C) bool qualify = false;
D) Random rand = new Random();

Question 14

A(n) ____________ is a special value that links a variable to an object.

A) linker
B) reference
C) operator
D) delimiter

Question 15

A variable that is used to reference an object is commonly called a(n) ____________.

A) reference variable
B) object variable
C) class variable
D) Boolean variable

Question 16

Each element in an array is assigned a unique number known as a(n) ____________.

A) subscript
B) identifier
C) delimiter
D) vector

Question 17

Look at the following code sample: const int SIZE = 10;
Int[] values = new int[SIZE];
For (int index = 0; index < SIZE; index++)
{
Values[index] = index + 1;
}
When the loop is finished stepping through the values array, what value will be stored in values[0]?

A) 10
B) 11
C) 0
D) 1

Question 18

Which one of the following statements declares a reference variable named values that can be used to reference an int array?

A) int values[];
B) values[int];
C) int[] values;
D) int [values];

Question 19

When working with an array, it is important that you do not use a(n)____________.

A) invalid subscript
B) null value
C) assignment statement
D) initialization list

Question 20

Which one of the following statements assigns the value 40 to the first element in an int array named values?

A) values[-1] = 40;
B) values[0] = 40;
C) values[null] = 40;
D) values[1] = 40;

Question 21

____________ is a process that periodically runs, removing all unreferenced objects from memory.

A) System cleanup
B) Garbage collection
C) Nullification
D) Non-maskable Interrupt

Question 22

The ____________ is a clever algorithm that is much more efficient that the sequential search.

A) random search
B) quick sort
C) binary search
D) combinatorial search

Question 23

C# provides a special loop known as the ____________, that automatically iterates once for each element in the array.

A) do-while loop
B) foreach loop
C) for loop
D) while loop

Question 24

Various techniques known as ____________ have been developed to locate a specific item in a larger collection of data, such as an array.

A) search engine schematics
B) search algorithms
C) database logic
D) referential protocols

Question 25

The foreach loop is designed to work with a temporary, read-only variable known as the ____________.

A) loop variable
B) counter variable
C) iteration variable
D) foreach variable

Question 26

To declare a two-dimensional array, two ____________ are required: The first one is for the number of rows, and the second one is for the number of columns.

A) reference variables
B) Boolean variables
C) named constants
D) size declarators

Question 27

To successfully ____________ the contents of two variables, we need a third variable that can serve as a temporary storage location.

A) copy
B) swap
C) reference
D) remove

Question 28

To compare the contents of two arrays, you must compare the ____________ of the two arrays.

A) memory locations
B) reference variables
C) elements
D) size

Question 29

In C#, all arrays have a(n) ____________ that is set to the number of elements in the array.

A) Element property
B) getSize method
C) Length property
D) GetBounds method

Question 30

When you call a method and pass an array as an argument, you simply pass the____________ that references the array.

A) data
B) method
C) variable
D) class

Question 31

When you process a(n) ____________, you must process only the elements that contain valid items.

A) partially filled array
B) reference copy
C) sequential search
D) Boolean expression

Question 32

____________ arrays, which are also called 2D arrays, can hold multiple sets of data.

A) Double-data
B) Two-dimensional
C) Row-column
D) Duel-derivative

Question 33

A(n) ____________ occurs when a loop iterates one time too many or one time too few.

A) off-by-one error
B) buffer overrun
C) system crash
D) logic error

Question 34

When only a reference of an object is copied and not the contents of the object itself, it is called a(n) ____________.

A) shadow copy
B) memory copy
C) error copy
D) reference copy

Question 35

The ____________ uses a loop to sequentially step through an array, starting with the first element.

A) sequential search algorithm
B) top-down algorithm
C) simple search algorithm
D) basic array traversal algorithm

Question 36

Because arrays are always passed ____________, a method that receives an array as an argument has access to the actual array.

A) by value
B) globally
C) in memory
D) by reference

Question 37

The ____________ works like this: The smallest value in the array is located and moved to element 0. The next smallest value is located and moved to element 1. This process continues until all the elements have been placed in their proper order.

A) bubble sort
B) binary search
C) Boolean swap
D) selection sort

Question 38

Look at the following code sample: int[] numbers = { 1, 2, 3, 4, 5 };
Int highest = numbers[0];
For (int index = 1; index < numbers.Length; index++)
{
If (numbers[index] > highest)
{
Highest = numbers[index];
}
}
What value will the highest variable contain when the loop finishes?

A) 1
B) 3
C) 5
D) 15

Question 39

With what value should the accumulator variable be initialized to calculate the total of the values in a numeric array?

A) null
B) false
C) 0
D) -1

Question 40

____________ arrays can only hold one set of data.

A) One-dimensional
B) Two-dimensional
C) Data bound
D) Classical

Question 41

Look at the following code sample: const int ROWS = 2;
Const int COLS = 2;
Int[,] grid = new int[ROWS, COLS];
What is the total number of elements in the grid array?

A) 2
B) 4
C) 8
D) 16

Question 42

All the data types in C# − and the underlying .NET Framework − fall into two categories: value types and reference types.

Question 43

The memory that is allocated for a reference type variable is the actual location that will hold any value that is assigned to that variable.

Question 44

Reference variables can be used only to reference objects.

Question 45

If you want to remove all the items from a List, you can call the ____________ method.

A) Clear
B) Reset
C) ClearAll
D) NewList

Question 46

A(n) ____________ is similar to an array but offers many advantages over an array.

A) List object
B) Collection
C) Random object
D) jagged array

Question 47

A List object has a(n) ____________ that holds the number of items stored in the List.

A) Count property
B) Total property
C) reference variable
D) extra memory location

Question 48

To add items to an existing List object, you use the ____________.

A) += operator
B) & operator
C) Insert property
D) Add method

Question 49

You can use the ____________ to remove an item at a specific index in a List.

A) Delete method
B) RemoveAt method
C) null keyword
D) Erase property

Question 50

You can store a mixture of data types in an array.

Question 51

You can use the ____________ to insert an item at a specific index in a List.

A) + operator
B) Add method
C) Insert method
D) Place property

Question 52

Traditional two-dimensional arrays, where each row has the same number of columns, are sometime referred to as ____________.

A) square arrays
B) rectangular arrays
C) box arrays
D) 2D arrays

Question 53

Because variables hold only a single value, they can be cumbersome in programs that process lists of data.

Question 54

Look at the following code sample: const int ROWS = 8;
Const int COLS = 2;
Int[,] table = new int[ROWS, COLS];
Which one of the following statements stores the value 25 in the element located at the first row and second column of the table array?

A) table[1, 2] = 25;
B) table[0, 1] = 25;
C) table[2, 1] = 25;
D) table[1, 0] = 25;

Question 55

Which one of the following statements creates a List object, named friendsList, that can be used to hold strings?

A) string friendsList = new List;
B) friendsList(string);
C) List friendsList = new List;
D) List friendsList = new List();

Question 56

List objects, like arrays, are always passed to a method ____________.

A) by value
B) in memory
C) by reference
D) globally

Question 57

A(n) ____________ is similar to a two-dimensional array, but the rows can have a different number of columns.

A) offset array
B) skewed array
C) jagged array
D) differential array

Question 58

Look at the following code sample: int[,] values = { { 1, 2, 3, 4 },
{ 5, 6, 7, 8 } };
What is the value stored in values[2, 2]?

A) 2
B) 3
C) 6
D) 7

Question 59

If you know the value of the item that you want to remove from a List, but you do not know the item's index, you can use the ____________.

A) - operator
B) Erase method
C) Remove method
D) -= operator

Question 60

Creating a reference type object typically requires the following two steps:
1. You declare a reference variable.
2. You create the object and associate it with the reference variable.

Question 61

When processing the contents of an array, there are some circumstances in which the foreach loop is not adequate, and the for loop should be used instead.

Question 62

When you use either the ref or out keywords with an array parameter, the receiving method not only has access to the array, but it also has access to the reference variable that was used to pass the array.

Question 63

When working with an array, you cannot use a subscript that is less than 0 or greater than the size of the array minus 1.

Question 64

The first element in an array is assigned the subscript 1, the second element is assigned the subscript 2, and so forth.

Question 65

Writing the contents of an array to a file is a straightforward procedure: Open the file and use a loop to step through each element of the array, writing its contents to the file.

Question 66

Arrays are reference type objects.

Question 67

Arrays are always passed by value.

Question 68

Because subscript numbering starts at 0, the subscript of the last element in an array is 1 less than the total number of elements in the array.

Question 69

The sequential search algorithm is the simplest of all search algorithms.

Question 70

Because array subscripts start at 1 rather than 0, you are not as likely to perform an off-by-one error.

Question 71

The default value of a string array's elements is null.

Question 72

An array's size declarator must be a nonnegative integer number.

Question 73

You access the individual elements in an array by using their subscripts.

Question 74

An array's Length property is read only, so you cannot change its value.

Question 75

In C#, you cannot reassign an array reference variable to a different array.

Question 76

The ref keyword creates and object in memory and returns a reference to the object it creates.

Question 77

You can create an array to hold any one type of value.

Question 78

When reading the contents of a file into an array, the loop should iterate until either the array is filled or the end of the file is reached.

Question 79

Because the foreach loop automatically knows the number of elements in an array, you do not have to use a counter variable to control its iterations, as with a regular for loop.

Question 80

If you provide an initialization list when declaring an array, you can leave out the size declarator, but you cannot leave out the new operator and its subsequent expression.