How do referenced types differ from primitive types?
Primitive types are integers.
Referenced types are strings.
Primitive types use memory addresses.
Referenced types use pointers to addresses.
Why do programmers use data structures rather than individual values?
for reduced storage
for multiple data types
for ease of access
Which data type only uses one bit per instance?
Short
char
double
boolean
Which data type uses the most storage per value?
short
int
long
float
What is the output of the following JavaScript code? var Salutations = [["Dear", "Hello", "Howdy"], ["Friend", "Judy", "Concerned", "Good Old Pal"]] console.log(Salutations[1][1])
Dear
Judy
Friend
Hello
How many elements are there in a two-dimensional array with length (4,7)?
21
4
7
28
What is the output of the following Swift code? var noKeys = [5,4,7,8,10,22] var noChains=noKeys.count print(noChains)
22
6
Why is a linear search slow?
It uses conditional statements.
It tests every element.
It copies the array.
Why should you exercise restraint and care in the use of mutable arrays?
The syntax for their use is extremely tedious and sensitive.
Their use can slow down performance dramatically.
The code may become difficult to translate to other languages.
What is the output of the following C# code? using System; class Program { static void Main() { int[ ][ ] jagged = new int[3][]; jagged[0]=new int[4]; jagged[1] = new int[2]; jagged[2]=new int[7]; Console.WriteLine(jagged[1][1]); }}
3
2
0
What is the defining characteristic of a jagged, two-dimensional array?
The length in the second dimension is variable.
The elements consist of strings.
The elements are of different data types.
The size of the array is not fixed.
What is the time complexity for a linear search if the value is not present?
O(ln(n))
O(n)
O(1)
O(n ln(n))
How are data elements referenced in an array?
by value
with an index or key
with a size or type
by name
What is returned by MyList.contains("Buy glue") if you are using java.util.LinkedList?
a Boolean
a string
an integer
Where does the following Java code add a new element to a linked list?
Node nodeToAdd = new Node(data); nodeToAdd.next = this.head; this.head = nodeToAdd;
at the end of the list
at the head of the list
in the middle of the list
What is the time complexity for insertion into a linked list?
How does Python implement linked lists?
as doubly linked lists
as arrays
as strings
What is required to change a singly linked list to a doubly linked list?
a two-dimensional array
pointers to adjacent nodes
a second head node and reverse pointers
a tail node and pointers to previous nodes
You have just added a new element at the end of an existing linked list. What is in the pointer of that new element?
the address of the first element in the list
a null value
the address of the last element in the list
What is contained in a node of a linked list?
a value and an index
a string and an integer
data and a pointer
an array and a size
How do queues differ from stacks?
Queues use FIFO and stacks use LIFO.
Queues use LIFO and stacks use FIFO.
Queues add and remove from the end of the list rather than from the beginning.
Stacks add and remove from different ends of the list rather than from the same end.
What is wrong with the following Java code?
import java.util.Stack; public class MyClass { public static void main(String args[]) { Stack myStack = new Stack(); myStack.push("test"); myStack.pop(); myStack.pop();
There is a missing ;.
It attempts to push to an empty stack.
There is an extra {.
It attempts to pop from an empty stack.
The following Swift code uses the push and pop functions as in the example. What is the value of SecondPop?
var deck:Stack=Stack() deck.push(item: "Queen: Spades") deck.push(item "10: Diamonds") deck.push(item: "4: Hearts") deck.push(item: "2: Hearts") var FirstPop = deck.pop() var SecondPop= deck.pop()
10: Diamonds
Queen: Spades
4: Hearts
2: Hearts
In the Swift code func pop()-> String?, what does the question mark mean?
The function may sometimes fail.
The length of the string is unknown.
The value returned is either a string or nil.
The argument of the function is unknown.
Which data structure is most useful for reversing an ordered state or list?
a queue
a stack
an array
What does LIFO stand for?
least important for order
limit in free order
least in first on
last in first out
How are items with the same priority dequeued from priority queues?
by FIFO
by LIFO
by size
The following Swift code uses the Queue class as in the example. What does the print() function output?
var yourQueue = Queue() yourQueue.enqueue(item: "10") yourQueue.enqueue(item: "5") yourQueue.enqueue(item: "8") var OutZero yourQueue.dequeue() var OutOne = yourQueue.dequeue() print(yourQueue.peek()!)
10
8
nil
5
What does a peek() return from a queue?
the first item
an arbitrary item
the last item
the middle item
Which language has the least support for hash functions and tables?
Python
Swift
Javascript
Java
Which line in the following Python 3 code produces a Key Error?
CapitalsToStates["Austin"] = "Texas"
print(CapitalsToStates["New York"])
CapitalsToStates = {}
print(CapitalsToStates["Austin"])
Why would you use separate chaining?
to increase access speed
to resolve a collision
to calculate a remainder
to generate a small index
When do hash tables suffer in performance?
when the keys are excessively long
when there are collisions
when the table is very large
How does hashing differ from encrypting?
Encrypting is reversible, but hashing is not.
Encrypting produces plain text, but hashing produces integers.
Hashing uses ASCII, and encrypting does not.
Hashing produces unique values, but encrypting does not.
Which statement is true for associative arrays?
Values must be ordered.
Keys must be unique.
Values must be unique.
Keys must be ordered.
Which statement is true for a tree data structure?
A parent can have only two children.
Leaves can have many children.
The root does not have a parent.
A node cannot be both a parent and a child.
What does the following Python 3 code output?
pocketContents=set(["keys","coins","knife"]) pocketContents.add("receipt") pocketContents.add("string") print(pocketContents)
{'receipt', 'coins', 'keys', 'string'}
{'receipt', 'coins', 'keys', 'string', 'knife'}
{'string', 'knife'}
{'receipt', 'coins', 'keys', 'knife'}
Which list constitutes a valid set containing four elements?
{0, 5, 12, 0}
{"four", "twelve", 6, "four"}
{"dog", "cat", "dog", "car"}
{0, "dog", "car", 7}
What characterizes a min heap?
The children have values less than those of their parents.
The value of the right child is less than that of the left.
The root contains the largest value.
The root contains the lowest value.
Why are binary search trees organized with the left child less than the parent and the right child greater than the parent?
to have more layers or branches
to reduce storage requirements
to use fewer pointers
to make them easy to search