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* Update en/Data Structures/Linked Lists/Circular Linked List.md

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* Update en/Data Structures/Linked Lists/Circular Linked List.md

Co-authored-by: David Leal <halfpacho@gmail.com>
Co-authored-by: Vitor Oliveira <vbrazo@gmail.com>

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en/Data Structures/Linked Lists/Circular Linked List.md

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+# Circular Linked List
+
+Circular Linked List is an end-connected data structure made of Nodes. Similar to the linear and doubly linked list, each node is composed of a variable ```data``` where its content is stored and a pointer to the next Node on the list. 
+The Linked List has a ```pointer``` to the adjacent elements but the last node is connected towards the head node i.e the first node itself, thus forming a circular shape.
+
+### Advantages over Arrays & Linear Linked List & Doubly Linked List
+
+- Any node can be a starting point
+- Useful for implementation of queue
+- Circular lists are useful in applications to repeatedly go around the list
+- Circular Doubly Linked Lists are used for the implementation of advanced data structures like Fibonacci Heap.
+- The size of a linked list is not fixed (dynamic size)
+- Deleting and adding an element is not expensive compared to an array
+
+### Drawbacks
+
+- Circular lists are complex as compared to singly linked lists.
+- Reversing of circular list is a complex as compared to singly or doubly lists.
+- If not traversed carefully, then we could end up in an infinite loop
+- Elements can be accessed sequentially not randomly compared to an array
+- Extra memory allocation needs to be done for pointers which connects elements in a linked list
+
+### Time Complexity
+
+| Operation | Average | Worst |
+|-----------|---------|-------|
+| Initialize|   O(1)  |    -  |
+| Access    |   O(n)  |  O(n) |
+| Search    |   O(n)  |  O(n) |
+| Insertion |   O(1)  |  O(n) |
+| Deletion  |   O(1)  |  O(n) |
+
+### Real World Application
+
+- Allocating CPU to resources
+- Multiplayer Board games
+
+### SLL v.s. CLL
+
+![image](https://i0.wp.com/algorithms.tutorialhorizon.com/files/2016/03/Circular-Linked-List.png)
+
+### Example
+
+<u>Insertion</u>
+```java
+public void insertHead(int data)
+{
+	Node temp = new Node(data);
+	Node cur = head;
+	while(cur.getNext() != head)
+		cur = cur.getNext();
+	if(head == null)
+	{
+		head = temp;
+		head.setNext(head);
+	}
+	else
+	{
+		temp.setNext(head);
+		head = temp;
+		cur.setNext(temp);
+	}
+	size++;
+}
+ ```
+
+## Code Implementation Links
+
+- [JavaScript](https://github.com/TheAlgorithms/Javascript/blob/master/Data-Structures/Linked-List/SingleCircularLinkedList.js.js)
+- [C++](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/data_structures/cll/cll.cpp)
+- [Python](https://github.com/TheAlgorithms/Python/blob/master/data_structures/linked_list/circular_linked_list.py)
+
+## Video Explanation
+
+[Video explanation on YouTube](https://youtu.be/HMkdlu5sP4A)