Precourse1 in Swift

[paridhimalviya]

Exercise_1 : Implement Stack using Array.

Exercise_2 : Implement Stack using Linked List.

Exercise_3 : Implement Singly Linked List.

[super30admin]

The student's solution demonstrates a good understanding of linked lists and stacks, with implementations in Swift. Here's a detailed evaluation:

1. Correctness:

• The LinkedList implementation correctly handles append and prepend operations.
• The Stack implementation using an array is correct and follows standard practices.
• The LinkedListToStackAdapter correctly implements stack operations using a linked list.
• The SinglyLinkedList implementation correctly handles push and append operations.

2. Time Complexity:

• LinkedList operations (append/prepend): O(1)
• Stack operations (push/pop/peek): O(1)
• LinkedListToStackAdapter operations: O(1) for all operations
• SinglyLinkedList operations: O(1) for push/append

3. Space Complexity:

• All implementations use O(n) space where n is the number of elements.

4. Code Quality:

• Good use of Swift features like generics, extensions, and protocols.
• Clear separation of concerns between different data structures.
• Good documentation and comments explaining the code.
• Some minor issues:
  • In LinkedListToStackAdapter, the description property could be simplified by using the existing LLLinkedList's description.
  • Some redundant code between different linked list implementations (Node classes could potentially be shared).
  • The date in the file headers is incorrect (12/16/25 and 12/17/25).

5. Efficiency:

• The implementations are generally efficient.
• One potential optimization would be to share the Node class between different linked list implementations to reduce code duplication.
• The Stack implementation could benefit from making storage private to enforce encapsulation.

Overall, the solution is well-structured and demonstrates a good understanding of the concepts. The main areas for improvement are reducing code duplication and improving encapsulation.