WGU C949 DATA STRUCTURES AND
ALGORITHMS CERTIFICATION SCRIPT 2026
QUESTIONS WITH SOLUTIONS GRADED A+
◍ Clas interface.
Answer: Consists of the methods that a programmer calls to create, modify,
or access a class instance.
◍ Radix sort bucket.
Answer: A collection of integer values that all share a particular digit value.
Ex: Values 57, 97, 77, and 17 all have a 7 as the 1's digit, and would all be
placed into item 7 when subdividing by the 1's digit.
◍ Expression.
Answer: A combination of items such as variables, literals, and operators
that evaluates to a value. Can be just a literal, just a variable, or some
combination of variables, literals, and operators.
◍ NP-Complete.
Answer: A set of problems for which no known efficient algorithm exists.
◍ Heap.
Answer: A complete binary tree-based data structure.
◍ direct access table.
Answer: A hash table with a direct hash function.
◍ Graph Direction.
Answer: Undirected Graph : The graph in which all the edges are
bidirectional.Directed Graph : The graph in which all the edges are
unidirectional.
◍ dict methods.
, Answer: my_dict.clear()Removes all items from the dictionarymy_dict =
{'Bob': 1, 'Jane': 42}my_dict.clear()print(my_dict){}my_dict.get(key,
default)Reads the value of the key entry from the dict. If the key does not
exist in the dict, then returns default.my_dict = {'Bob': 1, 'Jane':
42}print(my_dict.get('Jane', 'N/A'))print(my_dict.get('Chad',
'N/A'))42N/Amy_dict1.update(my_dict2)Merges dictionary my_dict with
another dictionary my_dict2. Existing entries in my_dict1 are overwritten if
the same keys exist in my_dict2.my_dict = {'Bob': 1, 'Jane':
42}my_dict.update({'John': 50})print(my_dict){'Bob': 1, 'Jane': 42, 'John':
50}my_dict.pop(key, default)Removes and returns the key value from the
dictionary. If key does not exist, then default is returned.my_dict = {'Bob':
1, 'Jane': 42}val = my_dict.pop('Bob')print(my_dict){'Jane': 42}
◍ Root.
Answer: In a binary tree, the one node with no parent.
◍ Percolating.
Answer: The upward movement of a node in a max-heap
◍ Binary Tree.
Answer: In a list, each node has up to one successor. In a binary tree, each
node has up to two children, known as a left child and a right child. "Binary"
means two, referring to the two children.
◍ Algorithm.
Answer: Describes a sequence of steps to solve a computational problem or
perform a calculation.
◍ modulo hash function.
Answer: computes a bucket index from the items key.It will map (num_keys
/ num_buckets) keys to each bucket.ie... keys range 0 to 49 will have 5 keys
per bucket. = 5
◍ Array in Java.
Answer: generic class that supports different data types. declared as follows,
where T is the data type.
, ◍ Positional list.
Answer: A list where elements contain pointers to the next and/or previous
elements in the list.
◍ Priority Queue.
Answer: A queue where each item has a priority, and items with higher
priority are closer to the front of the queue than items with lower priority.
Duplicates items are allowed.
◍ Doubly-linked lists.
Answer: In a previous section, the LinkedList class was defined, making use
of the Node class. The Node class defined previously can be extended from
the singly-linked list version to include a reference variable called prev that
refers to the previous node in the list. When a new node is first constructed,
the prev variable is assigned with None.Creating a doubly-linked node or a
doubly-linked list is still the same as creating a singly-linked node and a
singly-linked list.A linked list's head node does not have a previous node,
thus the prev data member has a value of None.
◍ Stack.
Answer: An ADT in which items are only inserted on or removed from the
top of a stack. *Last-in First-OutUnderlying data structures: Linked
listPush(stack, x), pop(stack), peek(stack), IsEmpty(stack),
GetLength(stack)*Pop & peek should not be used on a empty stack.
◍ Character index.
Answer: The position of a character in a string.
◍ Bucket sort algorithm.
Answer: *Look for something that distributes the values into "buckets"
where they are individually sorted. *Bucket sort is mainly useful when input
is uniformly distributed over a range.The bucket index is calculated as
number (N−1)/M N =number of bucketsM =maximum value of Mie 71
and 99 placed in the same bucket?71 bucket 2 71 * (5-1) // 99 =
2BucketSort(numbers, numbersSize, bucketCount) { if (numbersSize < 1)
ALGORITHMS CERTIFICATION SCRIPT 2026
QUESTIONS WITH SOLUTIONS GRADED A+
◍ Clas interface.
Answer: Consists of the methods that a programmer calls to create, modify,
or access a class instance.
◍ Radix sort bucket.
Answer: A collection of integer values that all share a particular digit value.
Ex: Values 57, 97, 77, and 17 all have a 7 as the 1's digit, and would all be
placed into item 7 when subdividing by the 1's digit.
◍ Expression.
Answer: A combination of items such as variables, literals, and operators
that evaluates to a value. Can be just a literal, just a variable, or some
combination of variables, literals, and operators.
◍ NP-Complete.
Answer: A set of problems for which no known efficient algorithm exists.
◍ Heap.
Answer: A complete binary tree-based data structure.
◍ direct access table.
Answer: A hash table with a direct hash function.
◍ Graph Direction.
Answer: Undirected Graph : The graph in which all the edges are
bidirectional.Directed Graph : The graph in which all the edges are
unidirectional.
◍ dict methods.
, Answer: my_dict.clear()Removes all items from the dictionarymy_dict =
{'Bob': 1, 'Jane': 42}my_dict.clear()print(my_dict){}my_dict.get(key,
default)Reads the value of the key entry from the dict. If the key does not
exist in the dict, then returns default.my_dict = {'Bob': 1, 'Jane':
42}print(my_dict.get('Jane', 'N/A'))print(my_dict.get('Chad',
'N/A'))42N/Amy_dict1.update(my_dict2)Merges dictionary my_dict with
another dictionary my_dict2. Existing entries in my_dict1 are overwritten if
the same keys exist in my_dict2.my_dict = {'Bob': 1, 'Jane':
42}my_dict.update({'John': 50})print(my_dict){'Bob': 1, 'Jane': 42, 'John':
50}my_dict.pop(key, default)Removes and returns the key value from the
dictionary. If key does not exist, then default is returned.my_dict = {'Bob':
1, 'Jane': 42}val = my_dict.pop('Bob')print(my_dict){'Jane': 42}
◍ Root.
Answer: In a binary tree, the one node with no parent.
◍ Percolating.
Answer: The upward movement of a node in a max-heap
◍ Binary Tree.
Answer: In a list, each node has up to one successor. In a binary tree, each
node has up to two children, known as a left child and a right child. "Binary"
means two, referring to the two children.
◍ Algorithm.
Answer: Describes a sequence of steps to solve a computational problem or
perform a calculation.
◍ modulo hash function.
Answer: computes a bucket index from the items key.It will map (num_keys
/ num_buckets) keys to each bucket.ie... keys range 0 to 49 will have 5 keys
per bucket. = 5
◍ Array in Java.
Answer: generic class that supports different data types. declared as follows,
where T is the data type.
, ◍ Positional list.
Answer: A list where elements contain pointers to the next and/or previous
elements in the list.
◍ Priority Queue.
Answer: A queue where each item has a priority, and items with higher
priority are closer to the front of the queue than items with lower priority.
Duplicates items are allowed.
◍ Doubly-linked lists.
Answer: In a previous section, the LinkedList class was defined, making use
of the Node class. The Node class defined previously can be extended from
the singly-linked list version to include a reference variable called prev that
refers to the previous node in the list. When a new node is first constructed,
the prev variable is assigned with None.Creating a doubly-linked node or a
doubly-linked list is still the same as creating a singly-linked node and a
singly-linked list.A linked list's head node does not have a previous node,
thus the prev data member has a value of None.
◍ Stack.
Answer: An ADT in which items are only inserted on or removed from the
top of a stack. *Last-in First-OutUnderlying data structures: Linked
listPush(stack, x), pop(stack), peek(stack), IsEmpty(stack),
GetLength(stack)*Pop & peek should not be used on a empty stack.
◍ Character index.
Answer: The position of a character in a string.
◍ Bucket sort algorithm.
Answer: *Look for something that distributes the values into "buckets"
where they are individually sorted. *Bucket sort is mainly useful when input
is uniformly distributed over a range.The bucket index is calculated as
number (N−1)/M N =number of bucketsM =maximum value of Mie 71
and 99 placed in the same bucket?71 bucket 2 71 * (5-1) // 99 =
2BucketSort(numbers, numbersSize, bucketCount) { if (numbersSize < 1)
