CircularLinkedList.cpp

#include <iostream>
using namespace std;

class node{

    public:
    int data;
    node* next;

    node(int val){
        data = val;
        next = NULL;
    }
};

void insertAtHead(node* &head, int val){

    node* n= new node(val);

    if(head == NULL){
        n->next =n;
        head=n;
        return;
    }


    node* temp = head;

    while(temp->next != head){
        temp=temp->next;
        n->next = head;
        head = n;
    }
}


void insertAtTail(node* &head, int val){

    if(head == NULL){
        insertAtHead(head,val);
        return;
    }

    node* n = new node(val);
    node* temp = head;

    while (temp->next != head)
    {
        temp=temp->next;
    }

    temp->next = n;
    n-> next = head;
    
}


void deleteAthead(node* &head){
    node* temp = head;
    while(temp->next!=head){
        temp=temp->next;
    }

    node* todelete=head;
    temp->next=head->next;
    head=head->next;
}
//deleteing the last element
void deletion(node* &head, int pos){

    if(pos==1){
        deleteAthead(head);
        return;
    }

    node* temp = head;
    int count = 1;

    while(count != pos-1){
        temp=temp->next;
        count++;
    }

    node* todelete= temp->next;
    temp->next=temp->next->next;
}

void display(node* head){
    node* temp = head;
    do
    {
        cout << temp->data << " ";
        temp=temp->next;
    } while (temp!=head);
    cout << endl;
}


int main(){
    node* head = NULL;
    insertAtTail(head,1);
    insertAtTail(head,2);
    insertAtTail(head,3);
    insertAtTail(head,4);
    display(head);
    insertAtHead(head,5);
    display(head);
    deletion(head,5);
    display(head);
    
}