Linked Listify - codepath/compsci_guides GitHub Wiki

Unit 5 Session 2 (Click for link to problem statements)

U-nderstand

Understand what the interviewer is asking for by using test cases and questions about the problem.

• How should the function handle an empty list?
  • If the input list lst is empty, the function should return None since there would be no nodes to create.

P-lan

Plan the solution with appropriate visualizations and pseudocode.

General Idea: Convert an array of values into a linked list, starting with the first value as the head and linking subsequent values.

1) Check if the input list `lst` is empty and return `None` if true.
2) Create the head of the linked list with the first element of `lst`.
3) Traverse the remaining elements of `lst`, creating a new node for each and linking it to the list.
4) Return the head of the newly formed linked list.

⚠️ Common Mistakes

• Forgetting to handle the case of an empty input list, which should return None.
• Errors in linking nodes could lead to incorrect or incomplete linked list structure.

I-mplement

def list_to_linked_list(lst):
    if not lst:  # Check if the array is empty
        return None
    head = Node(lst[0])  # Create the head node with the first element
    current = head
    for value in lst[1:]:  # Iterate over the rest of the elements
        current.next = Node(value)  # Create a new node and link it
        current = current.next
    return head