Operator Overloading

Question 1

What is an example of an overloaded operator built into c++?

Answer 1

&laquo_space;stream insertion/bitwise left shift operator

Question 2

When do + and - perform differently?

Answer 2

Depending on arithmetic type (int, float, pointer)

Question 3

What is an alternative to overloaded operators?

Answer 3

Explicit function calls

Question 4

What namespace does string belong to?

Answer 4

std

Question 5

What overloaded operators does string provide?

Answer 5

Equality, relational, assignment, addition assignment, and subscript

Question 6

What is boolalpha?

Answer 6

Stream manipulator
Displays true or false instead of 1/0

Question 7

How to indicate string object literal?

Answer 7

Place letter s immediately following closing “ of string literal

Question 8

Member function of string that return substring?

Answer 8

substr

Question 9

Which string overloaded operator does not perform bounds checking?

Answer 9

[]

Question 10

How to bounds check with string?

Answer 10

Member function at returns reference if subscript is valid

Question 11

How to overload an operator?

Answer 11

Function definition with keyword operator followed by operator being overloaded

Question 12

Operators overloaded must be what type of member functions?

Answer 12

Non-static
Must be called on an object

Question 13

Which operators can be used on class objects without being defined?

Answer 13

=, &, and ,

Question 14

Can you change precedence or associativity by overloading?

Answer 14

No

Question 15

The number of operands an operator takes can…..

Answer 15

Not be changed

Question 16

Can you create new operators?

Answer 16

No

Question 17

Can you change the meaning of how an operator works on fundamental types?

Answer 17

No

Question 18

Which assignment operators must be declared as class members

Answer 18

(), [], ->

Question 19

Binary operator must be overloaded as a ___________ member function with one arg or as a ______ member function with two args (with one of the arguments a _______)

Answer 19

non-static
non-
Class object or reference to a class object

Question 20

Unary operators for a class can be overloaded as a __________ member function with no arguments or a _________ member function with one argument (which must be a _______)

Answer 20

non-static
non-
Object or reference to an object

Question 21

Why should member functions that implement overloaded operators be non-static?

Answer 21

So they can access the non-static data in each object of the class

Question 22

How to overload prefix and postfix operators?

Answer 22

Each must have a distinct signature.
Postfix must have second arg of type int for compiler to distinguish

Question 23

Dynamic memory management

Answer 23

Controls allocation and deallocation of memory for built in or user defined type

Question 24

Heap/free store

Answer 24

Memory assigned to a program to store dynamically allocated objects at execution time

Question 25

What does new operator do?

Answer 25

Allocates right amount of storage for object
Runs objects constructor
Returns pointer of correct type
Throws exception if not enough memory

Question 26

Delete operator

Answer 26

Destroys dynamically allocated object and frees space

Question 27

How can you improve performance of non-member operator functions?

Answer 27

Declare as friend

Question 28

How to obtain class arg of member functions explicitly?

Answer 28

The this pointer

Question 29

How to enable an operator to be commutative?

Answer 29

Overload as non-member function

Question 30

Conversion constructors

Answer 30

Turn objects of other types into objects of particular class
Ex: overloaded cast-operator functions

Question 31

What can be used as a conversion constructor?

Answer 31

Constructor called with a single argument

Question 32

Can a compiler call cast operators and conversion constructors ?

Answer 32

Implicitly when necessary

Question 33

Explicit constructors

Answer 33

Can’t be used in an implicit conversion

Question 34

Can you overload the function call operator? ()

Answer 34

Yes, allows arbitrary number of parameters