Implementing Doubly Linked List in C

# Introduction

In this project, you will learn how to implement a doubly linked list data structure in C. A doubly linked list is a type of linked list where each node contains pointers to both its predecessor and successor nodes, allowing for efficient traversal in both forward and backward directions.

## 👀 Preview

$ gcc test_list.c list.c -o test
$ ./test
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## 🎯 Tasks

In this project, you will learn:

- How to initialize a doubly linked list
- How to traverse the doubly linked list and execute a callback function for each node
- How to insert a new node after a given node in the doubly linked list
- How to insert a new node before a given node in the doubly linked list
- How to delete a node from the doubly linked list

## 🏆 Achievements

After completing this project, you will be able to:

- Understand the basic structure and operations of a doubly linked list
- Implement the core functions required for managing a doubly linked list
- Demonstrate the ability to work with pointers and dynamic memory allocation in C
- Apply your knowledge to fix and improve the provided doubly linked list implementation