Data Structures Final Exam

A node without children is called a

Leaf node

Most operations on singly linked structures run in

Linear time

The index-based operations on a linked implementation of a list run in

Linear time

The insert and remove operations on an array-based indexed list run in

Linear time

Most of the operations on a list iterator connected to a linked list run in

Constant time

Random access supports

Constant time access to data

In Python, a type conversion operation for two collections

Creates copies of the objects in the source collection and adds these new objects to a new instance of the destination collection

Assume that data are inserted into a binary search tree in the order D B A C F E G. A preorder traversal would return these data in the order

D B A C F E G

The array implementation of a stack places the top element at the

Position after the last element that was inserted

Operations that access list elements by moving a cursor are called

Position-based operations

A postorder traversal of an expression tree returns the expression in

Postfix form

A hierarchical collection can represent a

File directory system

When an array runs out of memory to hold data, it is best to create a new array that

Has twice as many as the old array

Operations that access list elements at integer positions are called

Index-based operations

The filter function creates a sequence of the

Items in a given collection that pass a Boolean test

Profiling

is a way to measure the time cost of an algorithm using the computer's clock to obtain an actual run time

An array length

is fixed in size after it is created

______________ is a strategy that saves computed values for subsequent use, so they will not have to be recomputed

memoization

What is the difference between a SHALLOW COPY and a DEEP COPY?

shallow copy- are NOT cloned before being added to a new list, are references to the objects being copied deep copy- clones its items before adding them to the new collection

___________ and ____________ is the two most significant resources that we try to optimize seriously in algorithm analysis.

time, memory

Which of the following link list operations has a running time of O(n) on average case?

- Access at ith position - Replacement at ith position - Insert at ith position - Remove from ith position

Which of the following array operations has a running time of O(1) on average case?

- Access at ith position - Replacement at ith position - Insert at logical end - Remove from logical end

Examples of queues are (choose all that apply):

- Customers waiting in a checkout line - A line of cabs - VIP lines and regular lines in the airport

Queues are also known as

- First-in first-out data structures - Last-in last-out data structures

Which of the following link list operations has a running time of O(1) on average case?

- Insert at beginning - Remove from beginning

Which of the following array operations has a running time of O(n) on average case?

- Insert at ith position - Increase capacity - Decrease capacity - Remove from ith position

Stacks are also known as

- Last-in first-out data structures - First-in last out data structures

The operations that modify a queue are called

- enqueue() and dequeue() - pop(0) and append() - add() and pop()

The operations that modify a stack are called

- push() and pop() - append() and pop()

Put these Big O categorization name into the right order from the fastest to the slowest

1. Constant 2. Logarithmic 3. Linear 4. Quadratic 5. Exponential 6. Combinatoric

Put these sorting algorithms into the right order from the fastest to the slowest according to their average case

1. Counting Sort 2. Merge Sort 3. Insertion Sort 4. Bubble Sort with Tweak 5. Bubble Sort 6. Selection Sort

Put these Big O growth functions into the right order from the fastest to the slowest

1. O(1) 2. O(log n) 3. O(sqrt(n)) 4. O(n) 5. O(n**2) 6. O(2**n) 7. O(n!) 8. O(n**n)

Sort this unit abstraction from the smallest unit to the largest unit

1. function and methods 2. classes 3. modules

The value of the postfix expression 5 6 + 2 * is

22

Each level k in a full binary tree contains

2^k + 1 nodes

Assume that data are inserted into a binary search tree in the order D B A C F E G. An inorder traversal would return these data in the order

A B C D E F G

Examples of stacks are

A deck of playing cards

The for loop on a list visits its items

At each position, from the first one through the last one

The worst-case running time of an insertion into a singly linked structure occurs when you insert

At the tail of the structure

Choose all the examples of a Hierarchical Collection

Binary Search Tree, Heap, Organizational Tree

The index operation on an array-based sorted list uses

Binary search

One of the important algorithm techniques is the divide and conquer methods. Explain divide and conquer with your own words and give an example.

Binary search, splits data into 2 parts

The == operation for two lists must

Compare pairs of items at each position for equality

The running time of the three queue mutator operations is

Constant

Arrays and linked structures are examples of

Data Structures

A linked list is best implemented with a

Doubly linked structure

Assume that data are inserted into a binary search tree in the order A B C D E F G. The structure of this tree resembles that of a

List

Examples of linear collections are

Lists and stacks

Choose all the HETEROGENEOUS data structures

Lists, Tuples, Sets, Dictionaries

Insertions and removals from a heap are

Logarithmic operations

A graph collection best represents a

Map of flight paths between cities

An array uses less memory than a singly linked structure when

More than half of its positions are occupied by data

Who is the author of a book entitled "Algorithms + Data Structures = Program"

Niklaus Wirth

Data in a singly linked structure are contained in

Nodes

The linked implementation of a queue uses

Nodes with a link to the next node and an external pointer to the first node and an external pointer to the last node

What is the Big O of the Recursive Fibonacci?

O(2**n)

What is the Big O of the binary search function?

O(log n)

What is the Big O of the merge sort function?

O(n log n)

The worst-case behavior of the search of a binary search tree is

O(n)

What is the Big O of the counting sort function?

O(n)

What is the Big O of the sequential search function?

O(n)

What is the Big O of the bubble sort function?

O(n**2)

What is the Big O of the bubble sort with a tweak function?

O(n**2)

What is the Big O of the insertion sort function?

O(n**2)

What is the Big O of the selection sort function?

O(n**2)

The positional list operation next has

One precondition that hasNext returns True

The map function creates a sequence of the

Results of applying a function to the items in a given collection

The distinguished node at the beginning or top of a tree is called the

Root node

Examples of unordered collections are

Sets and dictionaries

Choose all the examples of an Unordered Collection

Sets, Dictionaries, Bags

It requires constant time to remove the first item from a(n)

Singly linked structure

The items in a priority queue are ranked from

Smallest (lowest priority) to largest (highest priority)

The item removed from a min-heap is always the

Smallest item

Choose all the FUNDAMENTAL data structures in Python

Strings, Lists

Choose all the examples of a Linear Collection

Strings, Lists, Tuples, Stacks, Queues

Choose all the IMMUTABLE data structures

Strings, Tuples

In the circular array implementation of a queue

The front index chases the rear index around the array

A doubly linked structure allows the programmer to move

To the next node or the previous node from a given node

The == operation for two sets must

Verify that the sets are of the same size and that each item in one set is also in the other set

From a user's perspective, a collection is an abstraction, and for this reason, in computer science, collections are also called _________________________.

abstract data types

The operation that inserts an element after the tail of a list is called

add

How is a binary search tree different from a binary tree?

binary tree- a tree whose elements have at most 2 children binary search tree- type of binary tree in which each item in a node's left subtree is less than the item in that node, and each item in the node's right subtree is greater than the item in that node

_____________________ is a method of determining the efficiency of algorithm by counting their basic operation such as addition, multiplication, comparison using simple algebra, pencil and paper.

complexity analysis

Describe one benefit and one cost of a doubly linked structure, as compared to a singly linked structure. Give also an application of a doubly linked structure.

doubly linked structure benefit- accesses data in the next or previous node in constant time singly linked structure benefit- good to use when not accessing the last element because it runs in linear time, thus traversing the entire collection application of doubly linked structure- manages systems with smaller amounts of data for a faster runtime

A sorted collection imposes a ______________________ on its items.

natural ordering