DSA Exam Verified Questions and Answers 100% Correct A+ Graded

DSA Exam Verified Questions and Answers 100% Correct A+ Graded What is a node? - Answer- A building block of a linked list that contains data and a link (pointer to next node). What two fields are inside a node? - Answer- Data and link (pointer to next node). What does the head pointer store? - Answer- The address of the first node in the linked list. What does head_ptr == nullptr mean? - Answer- The linked list is empty. What is a cursor pointer? - Answer- A temporary pointer used to walk through the list without losing head_ptr. What is the traversal pattern for linked lists? - Answer- node* cursor = head_ptr; while(cursor != nullptr) { cursor = cursor-link; } Why do we use cursor instead of head_ptr? - Answer- Moving head_ptr would lose access to the start of the list. What is the runtime of traversing a linked list? - Answer- O(n), as you must visit every node. What does list_length() do? - Answer- Counts the number of nodes in a linked list. What is the runtime of list_length? - Answer- O(n). What are the steps for inserting at head? - Answer- 1. Create node 2. Set data 3. Link to old head 4. Move head pointer. What is the insert head pointer pattern? - Answer- new_node-link = head_ptr; head_ptr = new_node. What is the runtime of inserting at head? - Answer- O(1), constant time. What pointers are needed to insert in the middle? - Answer- Previous and current. What is the insert after pointer pattern? - Answer- new_node-link = previous-link; previous-link = new_node. What are the steps to delete the head node? - Answer- 1. Save head 2. Move head forward 3. Delete old node. What is the delete head pattern? - Answer- node* remove_ptr = head_ptr; head_ptr = head_ptr-link; delete remove_ptr. What is the runtime of deleting head? - Answer- O(1). What does new do? - Answer- Allocates memory on the heap. What does delete do? - Answer- Releases dynamically allocated memory. What happens if you forget delete? - Answer- Memory leak. Why can't we use local nodes? - Answer- Local variables disappear when the function ends. What is the linked list toolkit? - Answer- A collection of non-member helper functions used to manipulate linked lists. What are examples of toolkit functions? - Answer- list_length, list_head_insert, list_insert, list_remove, list_remove_all, list_search, list_locate, list_copy, list_clear. Are toolkit functions member functions? - Answer- No, they are non-member functions that operate on nodes. What is a deep copy? - Answer- Creating new nodes with copied data instead of copying pointers. Why is head2 = head1 bad? - Answer- Both lists point to the same nodes, changes affect both lists. What is a bag container? - Answer- A container that stores items without order, allowing duplicates. What variables are in a linked-list bag? - Answer- head_ptr and many_nodes. What is an advantage of a linked list bag? - Answer- No capacity limit; nodes are dynamically allocated. When must the Big Three be implemented? - Answer- When a class uses dynamic memory. What are the Big Three? - Answer- Copy constructor, assignment operator, destructor. What is the purpose of the copy constructor? - Answer- Creates a deep copy of an object.