Question 1

Which of the following statements about functional programming is false

Accepted Answer

A)  You do not need to specify how to iterate through the elements or declare and use any mutable (that is, modifiable) variables. This is known as internal iteration, because the library code (behind the scenes) iterates through all the elements to perform the task. 
B)  A key aspect of functional programming is immutability-not modifying the data source being processed or any other program state, such as counter-control variables in loops. This eliminates common errors that are caused by modifying data incorrectly. 
C)  A filter operation combines the elements of a collection into a single new value, typically using a lambda that specifies how to combine the elements. 
D)  A map operation results in a new collection in which each element of the original collection is mapped to a new value (possibly of a different type). The new collection has the same number of elements as the collection that was mapped. 
A)  You do not need to specify how to iterate through the elements or declare and use any mutable (that is, modifiable) variables. This is known as internal iteration, because the library code (behind the scenes) iterates through all the elements to perform the task. 
B)  A key aspect of functional programming is immutability-not modifying the data source being processed or any other program state, such as counter-control variables in loops. This eliminates common errors that are caused by modifying data incorrectly. 
C)  A filter operation combines the elements of a collection into a single new value, typically using a lambda that specifies how to combine the elements. 
D)  A map operation results in a new collection in which each element of the original collection is mapped to a new value (possibly of a different type). The new collection has the same number of elements as the collection that was mapped. B

Question 2

Class Enumerable provides static method ________ to produce an IEnumerable containing integer values in sequence.The first argument specifies the starting value and the second specifies the number of values to produce.

Accepted Answer

A)  Span 
B)  Sequence 
C)  Spread 
D)  Range 
A)  Span 
B)  Sequence 
C)  Spread 
D)  Range D

Question 3

Covariance works only with reference types that are related by a class hierarchy.

Accepted Answer

A) True 
 B)False  True

Question 4

All arrays implicitly inherit from which generic interface

Accepted Answer

A)  IList 
B)  IEnumerable 
C)  IEnumerator 
D)  a and b 
E)  a and c 
A)  IList 
B)  IEnumerable 
C)  IEnumerator 
D)  a and b 
E)  a and c

Question 5

Which of the following statements is false

Accepted Answer

A)  Prior to C# 6, you could use a fully braced collection initializer to initialize a Dictionary’s key–value pairs. For example, if you had a Dictionary named toolInventory, you could create and initialize it as follows:

var toolInventory = new Dictionary{
   {"Hammer", 13},
   {"Saw", 17},
   {"Screwdriver", 7}
}; 
B)  The code in a) is shorthand for creating the Dictionary then using its Add method to add each key–value pair. 
C)  C# 6’s index initializers enable you to clearly indicate the key and the value in each key–value pair as follows:

var toolInventory = new Dictionary{
   ["Hammer"] = 13,
   ["Saw"] = 17,
   ["Screwdriver"] = 7
}; 
D)  Prior to C# 6, any collection that defined an Add extension method could be initialized with a collection initializer. As of C# 6, the compiler also supports collection initializers for any collection that has an Add instance method. 
A)  Prior to C# 6, you could use a fully braced collection initializer to initialize a Dictionary’s key–value pairs. For example, if you had a Dictionary named toolInventory, you could create and initialize it as follows:

var toolInventory = new Dictionary{
   {"Hammer", 13},
   {"Saw", 17},
   {"Screwdriver", 7}
}; 
B)  The code in a) is shorthand for creating the Dictionary then using its Add method to add each key–value pair. 
C)  C# 6’s index initializers enable you to clearly indicate the key and the value in each key–value pair as follows:

var toolInventory = new Dictionary{
   ["Hammer"] = 13,
   ["Saw"] = 17,
   ["Screwdriver"] = 7
}; 
D)  Prior to C# 6, any collection that defined an Add extension method could be initialized with a collection initializer. As of C# 6, the compiler also supports collection initializers for any collection that has an Add instance method.

Question 6

A _______ is the general term for a collection of key-value pairs.

Accepted Answer

A)  book 
B)  glossary 
C)  dictionary 
D)  lexicon 
A)  book 
B)  glossary 
C)  dictionary 
D)  lexicon

Question 7

Which of the following statements is false

Accepted Answer

A)  The LinkedList class is a singly linked list. 
B)  The LinkedList class's enumerator loops over the values of the nodes, not the nodes themselves. 
C)  One LinkedListNode cannot be a member of more than one LinkedList. 
D)  Method Find performs a linear search on the list and returns the first node that contains a value equal to the passed argument. 
A)  The LinkedList class is a singly linked list. 
B)  The LinkedList class's enumerator loops over the values of the nodes, not the nodes themselves. 
C)  One LinkedListNode cannot be a member of more than one LinkedList. 
D)  Method Find performs a linear search on the list and returns the first node that contains a value equal to the passed argument.

Question 8

Which of the following statements is false

Accepted Answer

A)  Lambda expressions allow you to define simple, anonymous methods. 
B)  A lambda's return type is listed to the left of the lambda. 
C)  A delegate can hold a reference to a lambda expression that has a signature that's compatible with the delegate type. 
D)  A lambda expression is called via a variable that references it. 
A)  Lambda expressions allow you to define simple, anonymous methods. 
B)  A lambda's return type is listed to the left of the lambda. 
C)  A delegate can hold a reference to a lambda expression that has a signature that's compatible with the delegate type. 
D)  A lambda expression is called via a variable that references it.

Question 9

Which of the following statements is false

Accepted Answer

A)  You filter elements to produce a collection of results that match a condition-known as a predicate. 
B)  LINQ extension method Where receives as its argument a Func delegate for a method that receives one argument and returns a bool indicating whether a given element should be included in the collection returned by Where. 
C)  The OrderBy extension method receives as its argument a Func delegate representing a method that receives one parameter (an element in the collection) and returns a value that's used to order the results. 
D)  Calls to Where and OrderBy are tuned to execute immediately at high performance. 
A)  You filter elements to produce a collection of results that match a condition-known as a predicate. 
B)  LINQ extension method Where receives as its argument a Func delegate for a method that receives one argument and returns a bool indicating whether a given element should be included in the collection returned by Where. 
C)  The OrderBy extension method receives as its argument a Func delegate representing a method that receives one parameter (an element in the collection) and returns a value that's used to order the results. 
D)  Calls to Where and OrderBy are tuned to execute immediately at high performance.

Question 10

Which of the following is not a collection class in C#

Accepted Answer

A)  ArrayList 
B)  HashTable 
C)  SortedDictionary 
D)  BitArray 
E)  None of the above 
A)  ArrayList 
B)  HashTable 
C)  SortedDictionary 
D)  BitArray 
E)  None of the above

Question 11

The compiler converts LINQ queries into calls to ________,many of which have delegate parameters.

Accepted Answer

A)  instance methods 
B)  constructors 
C)  extension methods 
D)  void methods 
A)  instance methods 
B)  constructors 
C)  extension methods 
D)  void methods

Question 12

Assigning an array of a derived-class type to an array variable of a base-class type is an example of contravariance.

Accepted Answer

A) True 
 B)False

Question 13

Which of the following statements is false

Accepted Answer

A)  A delegate is an object that holds a reference to a method. 
B)  Via delegates, you can assign methods to variables, and pass methods to and from other methods. 
C)  You can call methods through variables of delegate types. 
D)  All of the above statements are true. 
A)  A delegate is an object that holds a reference to a method. 
B)  Via delegates, you can assign methods to variables, and pass methods to and from other methods. 
C)  You can call methods through variables of delegate types. 
D)  All of the above statements are true.

Question 14

A _______ is one way to implement a dictionary

Accepted Answer

A)  hash table 
B)  linked list 
C)  stack 
D)  queue 
A)  hash table 
B)  linked list 
C)  stack 
D)  queue

Question 15

In functional programming,you specify ________ you want to accomplish in a task,but not ________ to accomplish it.

Accepted Answer

A)  how, what 
B)  when, how 
C)  what, when 
D)  what, how 
A)  how, what 
B)  when, how 
C)  what, when 
D)  what, how

Question 16

To initiate parallel processing,invoke IEnumerable extension method ________ (from class ParallelEnumerable),which returns a ParallelQuery.

Accepted Answer

A)  Parallel 
B)  AsConcurrent 
C)  AsParallel 
D)  Concurrent 
A)  Parallel 
B)  AsConcurrent 
C)  AsParallel 
D)  Concurrent

Question 17

Storing everything as objects in a collection will provide a performance boost.

Accepted Answer

A) True 
 B)False

Question 18

Which of the following is not a property of LinkedListNode

Accepted Answer

A)  Value 
B)  Reference 
C)  Previous 
D)  Next 
A)  Value 
B)  Reference 
C)  Previous 
D)  Next

Question 19

Classes which implement the IEnumerator interface must contain which of the following methods
A.MoveNext
B.Reset
C.Current
D.Reverse

Accepted Answer

A)  A, B, C 
B)  B, C, D 
C)  A, B, D 
D)  A, C, D 
A)  A, B, C 
B)  B, C, D 
C)  A, B, D 
D)  A, C, D

Question 20

Which of the following statements is false

Accepted Answer

A)  A concept called threads enables the operating system to run parts of an app concurrently. Though all of these tasks can make progress concurrently, they may do so by sharing one processor core. 
B)  With multicore processors, apps can operate truly in parallel on separate cores, possibly increasing the app's performance substantially. 
C)  Parallelizing apps and algorithms to take advantage of multiple cores is difficult and highly error prone, especially if those tasks share data that can be modified by one or more of the tasks. 
D)  A benefit of functional programming is that you can easily ask the library to perform a task with parallel processing to take advantage of a processor's multiple cores. This is the purpose of CLINQ (Concurrent LINQ)-an implementation of the LINQ to Objects extension methods that parallelizes the operations for increased performance. 
A)  A concept called threads enables the operating system to run parts of an app concurrently. Though all of these tasks can make progress concurrently, they may do so by sharing one processor core. 
B)  With multicore processors, apps can operate truly in parallel on separate cores, possibly increasing the app's performance substantially. 
C)  Parallelizing apps and algorithms to take advantage of multiple cores is difficult and highly error prone, especially if those tasks share data that can be modified by one or more of the tasks. 
D)  A benefit of functional programming is that you can easily ask the library to perform a task with parallel processing to take advantage of a processor's multiple cores. This is the purpose of CLINQ (Concurrent LINQ)-an implementation of the LINQ to Objects extension methods that parallelizes the operations for increased performance.

Exam 21: Collections

Which of the following statements about functional programming is false

Class Enumerable provides static method ________ to produce an IEnumerable< int > containing integer values in sequence.The first argument specifies the starting value and the second specifies the number of values to produce.

Covariance works only with reference types that are related by a class hierarchy.

All arrays implicitly inherit from which generic interface

Which of the following statements is false

A _______ is the general term for a collection of key-value pairs.

Which of the following statements is false

Which of the following statements is false

Which of the following statements is false

Which of the following is not a collection class in C#

The compiler converts LINQ queries into calls to ________,many of which have delegate parameters.

Assigning an array of a derived-class type to an array variable of a base-class type is an example of contravariance.

Which of the following statements is false

A _______ is one way to implement a dictionary

In functional programming,you specify ________ you want to accomplish in a task,but not ________ to accomplish it.

To initiate parallel processing,invoke IEnumerable< T > extension method ________ (from class ParallelEnumerable),which returns a ParallelQuery< T >.

Storing everything as objects in a collection will provide a performance boost.

Which of the following is not a property of LinkedListNode

Classes which implement the IEnumerator interface must contain which of the following methods A.MoveNext B.Reset C.Current D.Reverse

Which of the following statements is false

Introduction to Computers, the Internet and Visual C#

Dive Into Visual Studio Community

Introduction to C# Apps

Introduction to Classes,Objects,Methods and Strings

Control Statements: Part 1

Control Statements: Part 2

Methods: a Deeper Look

Arrays;Introduction to Exception Handling

Introduction to Linq and Generic Collections

Classes and Objects: A Deeper Look

Object-Oriented Programming: Inheritance

Object-Oriented Programming: Polymorphism

Exception Handling: A Deeper Look

GUI With Windows Forms: Part 1

GUI With Windows Forms: Part 2

Strings,Characters and Regular Expressions

Files and Streams

Searching and Sorting

Data Structures

Generics

Databases and LING

Asynchronous Programming With Async and Await

XML

GUI With Windows Presentation Foundation

Filters

In functional programming,you specify you want to accomplish in a task,but not to accomplish it.