Creating singly linked list program middle delete and middle insert program in c++

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/**
* C program to insert new node at the middle of Singly Linked List
*/

#include <iostream>
using namespace std;

/* Structure of a node */
struct node {
    int data;          // Data
    struct node *next; // Address
}*head;

void createList(int n);
void insertNodeAtMiddle(int data, int position);
void deleteMiddleNode(int position);
void displayList();

int main()
{
    int n, data, position;

    /*
     * Create a singly linked list of n nodes
     */
    cout<<("Enter the total number of nodes: ");
    cin>>(n);
    createList(n);

    cout<<("\nData in the list \n");
    displayList();

    /*
     * Insert data at middle of the singly linked list
     */
    cout<<("\nEnter data to insert at middle of the list: ");
    cin>>(data);
    cout<<("\nEnter the position to insert new node: " );
    cin>>(position);
    insertNodeAtMiddle(data, position);
   

    cout<<("\nData in the list \n");
    displayList();
cout<<("\nEnter the node position you want to delete: ");
    cin>>(position);

    /* Delete middle node from list */
    deleteMiddleNode(position);
    cout<<("\nData in the list \n");
    displayList();
    return 0;
}

/*
* Create a list of n nodes
*/
void createList(int n)
{
    struct node *newNode, *temp;
    int data, i;

    head = (struct node *)malloc(sizeof(struct node));

    /*
     * If unable to allocate memory for head node
     */
    if(head == NULL)
    {
        cout<<("Unable to allocate memory.");
    }
    else
    {
        /*
         * Input data of node from the user
         */
        cout<<("Enter the data of node 1: ");
        cin>>(data);

        head->data = data; // Link the data field with data
        head->next = NULL; // Link the address field to NULL

        temp = head;

        /*
         * Creates n nodes and adds to linked list
         */
        for(i=2; i<=n; i++)
        {
            newNode = (struct node *)malloc(sizeof(struct node));

            /* If memory is not allocated for newNode */
            if(newNode == NULL)
            {
                cout<<("Unable to allocate memory.");
                break;
            }
            else
            {
                cout<<"Enter the data of node"<<i<<":";
                cin>>(data);

                newNode->data = data; // Link the data field of newNode with data
                newNode->next = NULL; // Link the address field of newNode with NULL

                temp->next = newNode; // Link previous node i.e. temp to the newNode
                temp = temp->next;
            }
        }

        cout<<("SINGLY LINKED LIST CREATED SUCCESSFULLY\n");
    }
}

/*
* Creates a new node and inserts at middle of the linked list.
*/
void insertNodeAtMiddle(int data, int position)
{
    int i;
    struct node *newNode, *temp;

    newNode = (struct node*)malloc(sizeof(struct node));

    if(newNode == NULL)
    {
        cout<<("Unable to allocate memory.");
    }
    else
    {
        newNode->data = data; // Link data part
        newNode->next = NULL;

        temp = head;

        /*
         * Traverse to the n-1 position
         */
        for(i=2; i<=position-1; i++)
        {
            temp = temp->next;

            if(temp == NULL)
                break;
        }

        if(temp != NULL)
        {
            /* Link address part of new node */
            newNode->next = temp->next;

            /* Link address part of n-1 node */
            temp->next = newNode;

            cout<<("DATA INSERTED SUCCESSFULLY\n");
        }
        else
        {
            cout<<("UNABLE TO INSERT DATA AT THE GIVEN POSITION\n");
        }
    }
}

/*
* Display entire list
*/
void displayList()
{
    struct node *temp;

    /*
     * If the list is empty i.e. head = NULL
     */
    if(head == NULL)
    {
        cout<<("List is empty.");
    }
    else
    {
        temp = head;
        while(temp != NULL)
        {
            cout<<"Data="<< temp->data<<"\n"; // Print data of current node
            temp = temp->next;                 // Move to next node
        }
    }
}

/*
* Delete middle node of the linked list
*/
void deleteMiddleNode(int position)
{
    int i;
    struct node *toDelete, *prevNode;

    if(head == NULL)
    {
        cout<<("List is already empty.");
    }
    else
    {
        toDelete = head;
        prevNode = head;

        for(i=2; i<=position; i++)
        {
            prevNode = toDelete;
            toDelete = toDelete->next;

            if(toDelete == NULL)
                break;
        }

        if(toDelete != NULL)
        {
            if(toDelete == head)
                head = head->next;

            prevNode->next = toDelete->next;
            toDelete->next = NULL;

            /* Delete nth node */
            free(toDelete);

            cout<<("SUCCESSFULLY DELETED NODE FROM MIDDLE OF LIST\n");
        }
        else
        {
            cout<<("Invalid position unable to delete.");
        }
    }
}