Bağlı bir siyahını yerində yenidən düzəldin

#include <bits/stdc++.h>
using namespace std;

struct LLNode{
	int data;
	LLNode *next;	
};
// Function to create newNode in a linkedlist
LLNode* newNode(int data)
{
    LLNode *temp = new LLNode;
    temp->data = data;
    temp->next = NULL;
    return temp;
}
// Function to reverse the linked list
void reverselist(LLNode **head)
{
    // Initialize prev and current pointers
    LLNode *prev = NULL, *curr = *head, *next;
 
    while (curr)
    {
        next = curr->next;
        curr->next = prev;
        prev = curr;
        curr = next;
    }
 
    *head = prev;
}
// Function to rearrange a linked list
void rearrange(LLNode **head)
{
    // 1) Find the middle point using tortoise and hare method 
    LLNode *slow = *head, *fast = slow->next;
    while (fast && fast->next)
    {
        slow = slow->next;
        fast = fast->next->next;
    }
 
    // 2) Split the linked list in two halves
    LLNode *list1 = *head;
    LLNode *list2 = slow->next;
    slow->next = NULL;
 
    // 3) Reverse the second half
    reverselist(&list2);
 
    // 4) Merge alternate nodes
    *head = newNode(0); // Assign dummy Node
 
    // curr is the pointer to this dummy Node, which will
    // be used to form the new list
    LLNode *result = *head;
    while (list1 || list2)
    {
        // First add the element from first list
        if (list1)
        {
            result->next = list1;
            result = result->next;
            list1 = list1->next;
        }
 
        // Then add the element from second list
        if (list2)
        {
            result->next = list2;
            result = result->next;
            list2 = list2->next;
        }
    }
    // Assign the head of the new list to head pointer
    *head = (*head)->next;
}
void insertAtBeginning(LLNode**head,int dataToBeInserted)
{
	LLNode*curr=new LLNode;
	//make a new node with this data and next pointing to NULL
	curr->data=dataToBeInserted;
	curr->next=NULL;

	if(*head==NULL) //if list is empty then set the current formed node as head of list
			*head=curr;
		
	else //make the next of the current node point to the present head and make the current node as the new head
		{
			curr->next=*head;
			*head=curr;
		}
		
		//O(1) constant time
}


void display(LLNode**head)
{
	LLNode*temp=*head;
	while(temp!=NULL) //till the list ends (NULL marks ending of list)
		{
			if(temp->next!=NULL)
			cout<<temp->data<<" ->";
			else
			cout<<temp->data;
			
			temp=temp->next; //move to next node
		}
		//O(number of nodes)
	cout<<endl;
}

int main() 
{    
	
	LLNode *head = NULL; //initial list has no elements

	insertAtBeginning(&head,5);
	insertAtBeginning(&head,4);
	insertAtBeginning(&head,3);
	insertAtBeginning(&head,2);
	insertAtBeginning(&head,1);
	
	cout<<"\nCurrent List is :-\n";
	display(&head);
	rearrange(&head);
	cout<<"After rearranging the elements"<<endl;
	display(&head);
	return 0;
}