WGU C949 DATA STRUCTURES AND ALGORITHMS I OBJECTIVE ASSESSMENT EXAM 300 QUESTIONS AND CORRECT DETAILED ANSWERS WITH RATIONALES (VERIFIED ANSWERS) |AGRADE

WGU C949 DATA STRUCTURES AND ALGORITHMS I

OBJECTIVE ASSESSMENT EXAM 300 QUESTIONS AND

CORRECT DETAILED ANSWERS WITH RATIONALES

(VERIFIED ANSWERS) |AGRADE

What is a characteristic of keys in an associative dictionary data type? -

ANSWER- They are unique and immutable.

Which method can be used to take a value out of a dictionary? -

ANSWER- D1[key].remove(value)

Given this data dictionary in Python:

dict = {'white':0x0000, 'black':0x1111}

Which command/function generates the output ['white','black']? -

ANSWER- dict.keys()

Items were added sequentially in this stack starting with 'ham':

'sausage'

'toast'

'eggs'

'ham'

What is the correct order of contents after the push operation is

performed with the value 'bacon'? - ANSWER- 'bacon'

'sausage'

'toast'

'eggs'

'ham'

Items were added sequentially in this stack starting with "dog":

"bird"

"rabbit"

"cat"

"dog"

What is the return value of the pop operation? - ANSWER- "bird"

Which sequence of letters represents preorder traversal of the nodes of

this tree?

A

/ \

B C

/ \

/ \

D E

\ / \

F G H

/

I - ANSWER- A B C D F E G I H

An array soc of size 1009 is used where the index is an integer in

[0,1008] and the hash-function key09.

Where will the data associated with the key given by the last 4 social

security digits '2026' be stored? - ANSWER- In soc[5]

A stack s, a queue q, and a max value priority queue p each have a single

3 in them. Next s.push(4), q.push(4), and p.push(4) are executed.

What is the triple (s.pop(), q.pop(), p.pop())? - ANSWER- (4,3,4)

This stack reads left to right with the top to the right:

'green'

'yellow'

'blue'

'red'

What could be the stack after a push operation? - ANSWER-

['red','blue','yellow', 'green', 'purple"]

Items were added sequentially onto the stack starting with 'red':

'green'

'yellow'

'blue'

'red'

What is the stack after a pop operation? - ANSWER- 'yellow'

'blue'

'red'

Which command helps to speed up comparisons using dictionary keys

during a dictionary (d) lookup in this pseudocode clip?

h = hash(key)

for pair in d:

if h == pair[0]:

return pair[1] - ANSWER- hash(object)

What does the method any(b) return in Python if b is a dictionary? -

ANSWER- Returns True if any key of the dictionary is true.

Which Java method is used to read bytes from a standard file? -

ANSWER- Java.io.FileInputStream

Which command will retrieve an item from the top of the stack? -

ANSWER- Pop()

Which command will insert object x at position index in a list? -

ANSWER- Add(int index, Object x)

Which command will return true if x is in a list, otherwise return false? -

ANSWER- Contains(Object x)

When should a dictionary be used instead of a list? - ANSWER- When

the program uses key-value pairs as its data

The reference of the head of the doubly linked list is passed to the

reverse() method:

1<-->2<-->3<-->4<-->5<-->6

What is the modified linked list when complete? - ANSWER- 6<-->5<--

>4<-->3<-->2<-->1

Which data structure is indexed? - ANSWER- Array

Which data structure may only store homogeneous data elements? -

ANSWER- Arrays

What is a hierarchical data structure? - ANSWER- Tree

What is an attribute of a binary tree? - ANSWER- Each node has at most

two children.

Which data structure uses a last in, first out (LIFO) removal of items? -

ANSWER- Stack

Given:

heapList = [22, 33, 44, 55, 66]

Which index is the right child of item 22? - ANSWER- 44