Circular linked list in Data Structures Theory - Mini Project: Build & Apply

Understanding Circular Linked Lists

📖 Scenario: You are learning about circular linked lists, a special type of linked list where the last node points back to the first node, forming a circle. This structure is useful in real-world applications like music playlists that repeat or round-robin scheduling.

🎯 Goal: Build a simple circular linked list with three nodes and understand how the last node links back to the first node to form a circle.

📋 What You'll Learn

Create three nodes with values 10, 20, and 30

Link the nodes so that each points to the next

Make the last node point back to the first node to complete the circle

Define a variable to keep track of the head (first node)

💡 Why This Matters

🌍 Real World

Circular linked lists are used in applications like music players that repeat songs, or in scheduling algorithms where tasks are repeated in a cycle.

💼 Career

Understanding circular linked lists is important for software developers working with data structures, especially in systems programming, game development, and real-time applications.

1

Create three nodes with values

Create three variables called node1, node2, and node3. Assign each a dictionary with keys 'value' and 'next'. Set 'value' to 10, 20, and 30 respectively, and 'next' to None.

Data Structures Theory

# Create node1, node2, and node3 with values 10, 20, 30 and next set to None
# Your code here

Need a hint?

Each node is a dictionary with two keys: 'value' and 'next'. Start by setting 'next' to None.

2

Link nodes in sequence

Set node1['next'] to node2 and node2['next'] to node3 to link the nodes in order.

Data Structures Theory

node1 = {'value': 10, 'next': None}
node2 = {'value': 20, 'next': None}
node3 = {'value': 30, 'next': None}
# Link node1 to node2 and node2 to node3
# Your code here

Need a hint?

Use the 'next' key to point each node to the following node.

3

Complete the circle by linking last node to first

Set node3['next'] to node1 to make the list circular.

Data Structures Theory

node1 = {'value': 10, 'next': None}
node2 = {'value': 20, 'next': None}
node3 = {'value': 30, 'next': None}
node1['next'] = node2
node2['next'] = node3
# Link node3 back to node1 to form a circle
# Your code here

Need a hint?

Make the last node point back to the first node to complete the circle.

4

Define the head of the circular linked list

Create a variable called head and assign it to node1 to mark the start of the circular linked list.

Data Structures Theory

node1 = {'value': 10, 'next': None}
node2 = {'value': 20, 'next': None}
node3 = {'value': 30, 'next': None}
node1['next'] = node2
node2['next'] = node3
node3['next'] = node1
# Set head to node1
# Your code here

Need a hint?

The head variable helps us know where the circular linked list starts.