Doubly Linked List in Python

This project implements a Doubly Linked List (DLL) in Python with the following operations:

• Insert values (at beginning, end, or specific index)
• Remove values (from beginning, end, by index, or by value)
• Change a node’s value at a given index
• Reverse the list
• Search for values
• Get value at a specific index
• String representation of the list

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🐍 1. Basic Usage (easiest way)

If you just want to try the list without installing anything, copy doubly_linked_list.py into the same folder as your project and use:

from doubly_linked_list import DoublyLinkedList

dll = DoublyLinkedList()
dll.insert_at_end(10)
dll.insert_at_end(20)
dll.insert_at_beginning(5)

print(dll)  # Output: 5 <-> 10 <-> 20

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📦 2. Advanced Usage (install as a package)

If you want to use this as a Python package, you first need Git installed.
👉 Download Git if you don’t already have it.

Then install directly from GitHub using pip:

pip install git+https://github.com/Ahmedhm1/DLL---Doubly-Linked-List-Python.git

Now you can import it anywhere:

from dll import DoublyLinkedList

dll = DoublyLinkedList()
dll.insert_at_end(100)
dll.insert_at_end(200)
dll.insert_at_end(300)
print(dll)  # Output: 100 <-> 200 <-> 300

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🔎 Example Usage

from dll import DoublyLinkedList

# Create list and insert values
dll = DoublyLinkedList()
dll.insert_at_end(10)
dll.insert_at_end(20)
dll.insert_at_beginning(5)
dll.insert_at_index(15, 2)  # Insert 15 at index 2

print(dll)  # 5 <-> 10 <-> 15 <-> 20

# Remove values
dll.remove_start()   # Removes 5
dll.remove_end()     # Removes 20
dll.remove_value(15) # Removes node with value 15

# Change a value
dll.change_value(99, 0)  # Change first element to 99

# Reverse the list
dll.reverse()
print(dll)

# Search and get value
print(dll.search(99))       # Get index of value
print(dll.get_at_index(0))  # Get value at index 0

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📂 Project Structure

Doubly-Linked-List/
│
├── dll/       # Package source code
│   ├── __init__.py           # Exports DoublyLinkedList
│   └── doubly_linked_list.py # DLL implementation
│
├── README.md
├── pyproject.toml    # modern build file
└── setup.py          # Package setup script

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📖 Source Code

➡️ View doubly_linked_list.py directly if you just want to read the implementation.