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Rotate linked list clockwise by k nodes in c++

Rotating linked list node clockwise

C++ program for Rotate linked list clockwise by k nodes. Here mentioned other language solution.

// Include header file
#include <iostream>
using namespace std;
/*
  C++ program for 
  Rotate a list by moving each element 
  k times to the right.
  Or clockwise rotation of linked list 
*/
// Linked list node
class LinkNode
{
	public: 
    int data;
	LinkNode *next;
	LinkNode(int data)
	{
		this->data = data;
		this->next = nullptr;
	}
};
class SingleLL
{
	public: 
    LinkNode *head;
	LinkNode *tail;
	SingleLL()
	{
		this->head = nullptr;
		this->tail = nullptr;
	}
	// Add new Node at end of linked list 
	void addNode(int data)
	{
		LinkNode *node = new LinkNode(data);
		if (this->head == nullptr)
		{
			this->head = node;
		}
		else
		{
			// Append the node at last position
			this->tail->next = node;
		}
		this->tail = node;
	}
	// Display linked list element
	void display()
	{
		if (this->head == nullptr)
		{
			cout << "\n Empty linked list" << endl;
			return;
		}
		LinkNode *temp = this->head;
		// iterating linked list elements
		while (temp != nullptr)
		{
			cout << " " << temp->data << " →";
			// Visit to next node
			temp = temp->next;
		}
		cout << " NULL" << endl;
	}
	// This are perform the linked list rotation
	void rotation(int k)
	{
		// Define some auxiliary variable
		LinkNode *auxiliary = this->head;
		int count = 0;
		// Count number of node in linked list
		while (auxiliary != nullptr)
		{
			// visit to next node
			auxiliary = auxiliary->next;
			count++;
		}
		if (count <= 1)
		{
			// When have less than 2 nodes in linked list
			return;
		}
		// Get actual rotation
		count = k % count;
		if (count == 0)
		{
			// When actual linked list are not affected
			return;
		}
		auxiliary = this->head;
		// Find the rotational node
		while (count > 1)
		{
			// Visit to next node
			auxiliary = auxiliary->next;
			count--;
		}
		// Connecting the last node to first node of linked list
		this->tail->next = this->head;
		// Set new last node
		this->tail = auxiliary;
		// Set new head
		this->head = auxiliary->next;
		// Set that there is no node after of tail
		this->tail->next = nullptr;
	}
	// Handles the request to perform rotation
	// k is indicate node rotation
	void clockwiseRotation(int k)
	{
		if (k <= 0)
		{
			// When invalid given k
			return;
		}
		if (this->head == nullptr)
		{
			cout << "\n Empty Linked List" << endl;
			return;
		}
		// Display given linked list
		cout << " Before rotate " << endl;
		cout << " Linked List : " << endl;
		this->display();
		cout << " Given k : " << k << endl;
		// Perform rotation
		this->rotation(k);
		// Display resultant linked list
		cout << " After rotate " << endl;
		cout << " Linked List : " << endl;
		this->display();
		cout << "\n" << endl;
	}
};
int main()
{
	SingleLL *sll1 = new SingleLL();
	SingleLL *sll2 = new SingleLL();
	// First linked list
	// 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → NULL
	sll1->addNode(1);
	sll1->addNode(2);
	sll1->addNode(3);
	sll1->addNode(4);
	sll1->addNode(5);
	sll1->addNode(6);
	sll1->addNode(7);
	sll1->addNode(8);
	// Second linked list
	// 4 → 9 → 7 → 3 → 8 → 6 → -2 → NULL
	sll2->addNode(4);
	sll2->addNode(9);
	sll2->addNode(7);
	sll2->addNode(3);
	sll2->addNode(8);
	sll2->addNode(6);
	sll2->addNode(-2);
	// Test case
	sll1->clockwiseRotation(3);
	sll2->clockwiseRotation(18);
	return 0;
}

Output

 Before rotate
 Linked List :
 1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → NULL
 Given k : 3
 After rotate
 Linked List :
 4 → 5 → 6 → 7 → 8 → 1 → 2 → 3 → NULL


 Before rotate
 Linked List :
 4 → 9 → 7 → 3 → 8 → 6 → -2 → NULL
 Given k : 18
 After rotate
 Linked List :
 8 → 6 → -2 → 4 → 9 → 7 → 3 → NULL





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