Deck 8: Advanced Collections

Question 1

With a two dimensional array, when the number of columns in the rows differs, a jagged array can be created.

Answer 1

True

Question 2

In C#, a two-dimensional array is usually visualized as a table divided into columns and rows where data is stored in contiguous memory locations by column.

Answer 2

False

Question 3

The Queue class represents a Last In First Out (LIFO) collection of objects while the  Stack collection class represents a simple FIFO (First In First Out) collection.

Answer 3

False

Question 4

C# uses a row major format for accessing arrays, which means that the elements are printed in rows. Every entry in the first column is printed before moving to the second column.

Question 5

With C#, you are limited to 10 dimensions for multi-dimensional arrays.

Question 6

The string class stores an immutable series of characters--meaning once you assign a string reference a value, that referenced location's value cannot be modified.

Question 7

The GetLength( ) method can be called to return the number of rows or columns.

Question 8

The Length property can be used to return the total number of elements in all dimensions.

Question 9

The major requirement of dealing with multi-dimensional arrays is the fact that all data values placed in an array must be of the same base type.

Question 10

For a declaration such as, int [ , ]  anArray = new int [6, 5], a total of 11 memory locations can be accessed using the identifier anArray.

Question 11

double [  ,  ] price = new double [2 , 5] {{1.1, 1.2, 1.3, 1.5, 1.4}{2.1, 2.2, 2.3, 2.5, 2.4}};
With the declaration above, price[0,2] refers to 2.2.

Question 12

The Rank property is used with array collections to return the number of dimensions.

Question 13

The string is a reference type in C#.

Question 14

Console.WriteLine(calories.GetUpperBound(0)); returns the largest value in an array.

Question 15

double [  ,  ] price = new double [2 , 5] {{1.1, 1.2, 1.3, 1.5, 1.4}{2.1, 2.2, 2.3, 2.5, 2.4}};
Looking above, the value of price.Length is 10.

Question 16

In C#, you may access a two-dimensional array element using the notation [ , ] or through using a double set of braces ([ ] [ ]).

Question 17

double [  ,  ] price = new double [2 , 5] {{1.1, 1.2, 1.3, 1.5, 1.4}{2.1, 2.2, 2.3, 2.5, 2.4}};
With the declaration above, price[1] refers to 1.2.

Question 18

Collection classes are classes that enable you to store and retrieve various groups of objects.

Question 19

The foreach loop structure cannot be used to iterate through a multi-dimensional array.

Question 20

Multi-dimensional array identifiers are normally defined using a plural noun.

Question 21

Which of the following would define a two dimensional structure to store temperature during three periods of a day for seven days?

A) int [ , ] temp = new int [7, 3];
B) int [ , ] temp = new int [6, 2];
C) int  temp[7] [3 ] = new temp [7] [3];
D) int  temp[6] [2 ] = new temp [6] [2];

Question 22

Since the string data type is a reference type, you compare addresses as opposed to comparing contents or values when you use the equality operators with two string data items.

Question 23

C# has two types of string literals. Quoted string literals appear between double quotation marks (" ")  and verbatim string literal, which start with the at symbol (@).

Question 24

Normally you will want to use two integral values to reference individual elements in a two-dimensional array. If you use just one integral value, you get all of the values for that row.

Question 25

The string type allows individual characters to be accessed using an index with [ ].

Question 26

With a two-dimensional array, GetLength(0) returns the number of rows and GetLength(1) returns the number of columns in the array.

Question 27

Which of the following could be a method heading for a member method that returns a two-dimensional array?

A) int [ , ] void DoSomething( )
B) void  int [ , ] DoSomething( )
C) int [ , ] DoSomething( )
D) void DoSomething[ , ]

Question 28

There are several ways to do a compile-time initialization of two-dimensional arrays. All of the following are valid ways EXCEPT ____.

A) int [, ] anArray = {{100, 100, 100} {100, 100, 100}};
B) int [ , ] anArray = new int [ , ] {{100, 100, 100} {100, 100, 100}};
C) int [ ,  ] anArray = new int [2, 3 ] {{100, 100, 100} {100, 100, 100}};
D) int [ ] anArray = new int [10 ] {{100, 100, 100} {100, 100, 100}};

Question 29

The ArrayList class can be used to create a listlike structure that can dynamically increase or decrease in length.

Question 30

A two dimensional array is accessed much like you access cells in a spreadsheet.

Question 31

The ArrayList does not allow you to mix types. All elements must be of the same data type.

Question 32

A Hashtable represents a collection of key/value pairs that are organized based on the hash code of the key.

Question 33

If an array named num is dimensioned to hold 10 values in 5 rows and 2 columns, how would you store 50 in the first physical row and first physical column?

A) num[ 1, 1 ] = 50;
B) num[ 0 , 0 ] = 50;
C) num = 50 [ ] ;
D) num5 = 50;

Question 34

The ArrayList class requires you to add and remove elements to/from the structure using  Push( ) and Pop( ) methods.

Question 35

One of the special properties in the ArrayList class is Count. It returns ____.

A) an int representing the number of values currently stored in the array
B) an int representing the size the array was dimensioned
C) how much storage is consumed by the entire array
D) the length of an individual element of the array

Question 36

Which of the following is a valid example of calling a method and sending it a two-dimensional  array argument?

A) DisplayArrayContents(int [ ,  ] anArray);
B) DisplayArrayContents(anArray);
C) DisplayArrayContents(anArray[10, 2]);
D) DisplayArrayContents(int [10, 2] anArray);

Question 37

One of the properties of the ArrayList class is ____.  It Gets or sets the number of elements that the ArrayList can contain.

A) Length
B) Capacity
C) Rank
D) Count

Question 38

Which of the following is a valid heading for a method that could accept the two-dimensional array as an argument?

A) void DisplayOutput(double [ ,  ] anArray)
B) void DisplayOutput(double [10 , 2 ] anArray)
C) void DisplayOutput(double anArray)
D) void DisplayOutput(double anArray [10 , 2])

Question 39

BinarySearch( ) is ____.

A) a method in the ArrayList class
B) an instance method
C) usable with floating point type arrays
D) a method in the string class

Question 40

int [ , ] score = {{88, 66, 76, 92, 95} {67, 88, 45, 99, 80}}; int total = 0;
Foreach (int val in score)
Total += val;
Using the code shown above, what is added to total during the first iteration?

A) 0
B) 88
C) 86, 66, 76, 92 and 95
D) unknown, because val is not initialized

Question 41

Which of the following returns the number of columns in a two-dimensional array?

A) Rank
B) GetLength(0)
C) GetLength(1)
D) GetLength

Question 42

string [ , ] name = new string [2, 3] {{"Alex", "Ben", "Cay"}, {"Jose", "Tyne", "Yin" }};
Looking above, what does name[0, 1] reference?

A) l
B) Ben
C) Alex
D) Al

Question 43

The ____ method adds an object to the end of the queue.

A) Enqueue( )
B) Dequeue( )
C) Pop( )
D) Push( )

Question 44

The method that deletes a number of characters beginning at a specified position is ____.

A) Remove( )
B) Delete( )
C) Replace( )
D) ReplaceAt( )

Question 45

int [ , , ] anArray = new [3, 2, 7] allows ____ elements to be stored.

A) 42
B) 12
C) 7
D) 3

Question 46

string sValue = "Life is about choices";
String [ ] sn = sValue.Split(' ');
After the above segment of code is executed, where is "choices" stored?

A) sn[0]
B) sn[4]
C) sn[3]
D) sValue

Question 47

For a two-dimensional array, values are stored ____________ using a row major format.

Question 48

In order to determine the position of one or more characters inside a string argument, use the ____ method of the string class.

A) Location( )
B) Position ( )
C) IndexOf( )
D) Place( )

Question 49

Which of the following segments of code will display the first row of a two dimensional array?

A) for (int i = 0; i   Console.Write(anArray[0, i] + "\t");
B) for (int i = 0; i   Console.Write(anArray[0, i] + "\t");
C) for (int i = 0; i   Console.Write(anArray[i, 0] + "\t");
D) for (int i = 0; i   Console.Write(anArray[i, 0] + "\t");

Question 50

C# has two types of string literals. The @-quoted string literals are called ____.

A) quoted string literal
B) at string literal
C) actual string literal
D) verbatim string literal

Question 51

____ are types of data structures that consist of a sequence of data records such that in each record there is an additional field that contains a reference (i.e., a link) to the next record in the sequence.

A) Arrays
B) ArrayLists
C) Linked lists
D) Strings

Question 52

Which of the following is an example of a collection class?

A) Array
B) Queue
C) HashTable
D) all of the above

Question 53

Which method in the string class might be useful to create a table with values number aligned?

A) Align( )
B) Concat( )
C) PadLeft( )
D) Split( )

Question 54

Which class represents a First-In-First-Out (FIFO) collection, which is useful for storing objects in the order they were received for sequential processing?

A) Queue
B) HashTable
C) Stack
D) ArrayList

Question 55

Console.Write("AnExample".PadLeft(20, "#") returns ____.

A) ###########AnExample
B) AnExample###########
C)            AnExample
D) AnExample

Question 56

The method ____ of the ArrayList class returns an arraylist that is a subset of another arraylist.

A) GetSubList( )
B) InsertRange( )
C) SubList( )
D) GetRange( )

Question 57

Console.Write("anExample".IndexOf("a")); returns ____.

A) null
B) 4
C) 04
D) 0

Question 58

string sValue = "Life is about choices";
String [ ] sn = sValue.Split(' ');
Using the Substring( ) method with sValue, which of the following references the word choices?

A) sValue.Substring(14, 7);
B) sValue.Substring(3);
C) sValue.Substring("choices");
D) sValue.Substring(15, 7);

Question 59

The string method that retrieves part of a string from a string argument is ____.

A) Trim( )
B) Substring( )
C) Retrieve( )
D) IndexOf( )

Question 60

The method in the string class that returns the string in uppercase is ____.

A) StringUpper( )
B) Upper( )
C) ConvertToUpper( )
D) ToUpper( )

Question 61

The major requirement when working with arrays is the fact that all data values placed in an array must be of the ____________.

Question 62

If you override the GetHashCode( ) method, you must also override the ____________ method to guarantee that two objects considered equal have the same hash code. Both  are inherited from the object class.

Question 63

C# is a row major language, which means you specify the column index ____________ when you reference elements in a two-dimensional array.

Question 64

Strings are considered ____________ because once you give a string a value; it cannot be  modified. Methods that seem to be modifying a string are actually returning a new  string containing the modification.

Question 65

C# also includes a generic ____________ class that is very similar to the ArrayList class. The primary difference between the two classes is that objects do not have to be the same type when they are pushed on an ArrayList, unlike the other class, which requires all objects to be of the same type..

Question 66

As with the ArrayList class, in order to instantiate objects of many of the collection classes, you need to include a using ____________.

Question 67

Like traditional arrays, indexes of ArrayList objects are ____________.

Question 68

____________ class represents a simple last-in-first-out (LIFO) collection of objects.

Question 69

The property ____________ returns the number of dimensions of the array.

Question 70

In C#, the string type allows individual characters to be accessed using a(n) ____________ with the [ ].

Question 71

The ____________ are defined to compare the contents of strings instead of comparing their addresses.

Question 72

The ____________ property can be used with multidimensional arrays to get the total number of elements in all dimensions.

Question 73

The ____________ method is used with the ArrayList class to push items on the list.

Question 74

To declare a three-dimensional array, three integral values are used. The first number specifies the number of ____________.