0x12-more_singly_linked_lists

0x12. C - More singly linked lists

In computer science, a linked list is a linear collection of data elements, in which linear order is not given by their physical placement in memory. Instead, each element points to the next. It is a data structure consisting of a group of nodes which together represent a sequence. Under the simplest form, each node is composed of data and a reference (in other words, a link) to the next node in the sequence. This structure allows for efficient insertion or removal of elements from any position in the sequence during iteration. More complex variants add additional links, allowing efficient insertion or removal from arbitrary element references. A drawback of linked lists is that access time is linear (and difficult to pipeline). Faster access, such as random access, is not feasible. Arrays have better cache locality as compared to linked lists.

source: https://en.wikipedia.org/wiki/Linked_list

Exercises

0. Print list

Write a function that prints all the elements of a listint_t list.

• Prototype: size_t print_listint(const listint_t *h);
• Return: the number of nodes
• Format: see example
• You are allowed to use printf

1. List length

Write a function that returns the number of elements in a linked listint_t list.

• Prototype: size_t listint_len(const listint_t *h);

2. Add node

Write a function that adds a new node at the beginning of a listint_t list.

• Prototype: listint_t *add_nodeint(listint_t **head, const int n);
• Return: the address of the new element, or NULL if it failed

3. Add node at the end

Write a function that adds a new node at the end of a listint_t list.

• Prototype: listint_t *add_nodeint_end(listint_t **head, const int n);
• Return: the address of the new element, or NULL if it failed

4. Free list

Write a function that free a listint_t list.

• Prototype: void free_listint(listint_t *head);

5. Free

Write a function that free a listint_t list.

• Prototype: void free_listint2(listint_t **head);
• The function sets the head to NULL

6. Pop

Write a function that deletes the head node of a listint_t linked list, and returns the
head node’s data (n).

• Prototype: int pop_listint(listint_t **head);
• if the linked list is empty return 0

7. Get node at index

Write a function that returns the nth node of a listint_t linked list.

• Prototype: listint_t *get_nodeint_at_index(listint_t *head, unsigned int index)
• where index is the index of the node, starting at 0
• if the node does not exist, return NULL

8. Sum list

Write a function that returns the sum of all the data (n) of a listint_t linked list.

• Prototype: int sum_listint(listint_t *head);
• if the list is empty, return 0

9. Insert

Write a function that inserts a new node at a given position.

• Prototype: listint_t *insert_nodeint_at_index(listint_t **head, unsigned int idx, int n);
• where idx is the index of the list where the new node should be added. Index starts at 0
• Returns: the address of the new node, or NULL if it failed
• if it is not possible to add the new node at index idx, do not add the new node and return NULL

10. Delete at index

Write a function that deletes the node at index index of a listint_t linked list.

• Prototype: int delete_nodeint_at_index(listint_t **head, unsigned int index);
• where index is the index of the node that should be deleted. Index starts at 0
• Returns: 1 if it succeeded, -1 if it failed

AUTHOR

Adekunle Adeniran

Full stack software Engineer