C++ & Classes
Pointers & References
Memory
Operators & Big Three
Templates & Data Structures
100
Why would we write a class? (three reasons)
Avoid repeating code
Control access of certain variables and functions
Encapsulation
100
Why would we pass by reference instead of by value for most complex objects?
Avoid making a copy, which takes up a lot of memory
100
The "new" keyword does this.
What is allocating memory on the heap?
100
These are the Big Three.
What are Copy Constructor, Assignment Operator, and Destructor?
100
What is the access order of a queue?
FIFO
(First in, first out)
200
The last step in the C++ program compilation process.
What is linking?
200
What is printed?
int b = 5;
int* a = &b;
cout << a << endl;
Memory address of b
200
What is the main difference between the stack and the heap?
The stack is memory that is managed automatically based on scope, while heap memory is allocated and deallocated manually
200
Given this code snippet, what does "b.print()" output?
blue balloon holding 4.0
200
This feature is the reason why we don’t split template classes into .h and .cpp files.
What is the compiler?
300
Given the following class, what is printed?
CAR 0100560
MALA 321040
300
With respect to pointers, what do the operators -> and * do?
-> allows you to access an object variable or function through a pointer to that object.
* dereferences a pointer, giving you access to the object
300
In this class, what are the sizes (in bytes) of a char, a short, an int, and a pointer?
char: 1
short: 2
int: 4
pointer: 4
300
What is the expected return type of an overloaded /=, where T is the type of an object?
T&
300
What are the three differences between linked lists and arrays?
Linked Lists are not random access, but arrays are
Linked lists are non-contiguous, but arrays are contiguous
Linked lists require more memory space than linked lists.
400
What does the static keyword do when applied to a) a function, and b) a class?
a) It allows a variable to live longer than the function
b) It creates a variable shared by all instances of a class
400
Given the following code snippet:
8
400
On what line does an error first appear? What is the error? Why?
A segmentation fault occurs on "arr[1] = 16".
This is because we try to access memory that we are no longer using.
400
What member of the big 3 is called on line 5?
Copy constructor
400
Why could there be an error in this function?
Some classes don't have a getBool() function.
500
What is held constant in this function? What is returned?
int* const MyClass::func(const int* p) const;
The function has a const parameter and the object calling the function is held constant; the function returns a const pointer to an int.
500
What is printed?
7 6 5
500
How many bytes of memory are leaked?
16 bytes
500
What members of the big 3 are called on which lines?
Copy constructor - lines 2, 5, 7
Destructor - lines 9, 11, 12
500
Briefly explain how to insert a node into the middle of a singly Linked List.
First, iterate to one before where you want to insert the new node.
Then, point the new node’s next pointer to the current next node, and point the current node’s next pointer to the new node