message: added code in CPP
  I have added code in C++ programming language, i.e insert node at iTH position in a linked list.
diff: -//By Pratyaksh Khurana
  +
  +//Problem - Insert node at iTH position in a linked list
  +/*By Pratyaksh Khurana*/
  +
  +#include<bits/stdc++.h>
  +using namespace std;
  +
  + //class node for implementing linked list
  +class node
  +{
  +public:
  +
  + //value that the node contains
  + int data;
  +
  + //address of the next node
  + node *next;
  +
  + //constructor to initialising node
  + node(int data)
  + {
  + this->data = data;
  + next = NULL;
  + }
  +};
  +
  +
  +//Taking input in a linked list until user enters -1
  +node* input()
  +{
  + int data;
  + cin>>data;
  +
  + node *head = NULL;
  + node *tail = NULL;
  +
  + while(data != -1)
  + {
  + node *newnode = new node(data);
  +
  + if(head == NULL)
  + {
  + head = newnode;
  + tail = newnode;
  + }
  + else
  + {
  + tail->next = newnode;
  + tail = newnode;
  + }
  + cin>>data;
  + }
  + return head;
  +}
  +
  +//printing the linked list
  +void print(node *head)
  +{
  + while(head != NULL)
  + {
  + cout<<head->data<<" ";
  + head = head->next;
  + }
  +
  +}
  +
  +//insert node at a specific position by the user
  +node* insertNode(node *head,int i,int data)
  +{
  + //create new node;
  + node *insert_node = new node(data);
  +
  + int idx = 0;
  + node *temp = head;
  +
  + //edge case
  + if( i == 0)
  + {
  + insert_node->next = head;
  + head = insert_node;
  + return head;
  +
  + }
  +
  + while(temp != NULL && idx < i-1)
  + {
  + temp = temp->next;
  + idx++;
  + }
  +
  + //edge case
  + if(temp != NULL)
  + {
  + insert_node->next = temp->next;
  + temp->next = insert_node;
  + }
  + return head;
  +
  +}
  +
  +int main()
  +{
  +
  + //input linked list
  + node *head = input();
  + cout<<"Before insertion : ";
  + //print linked list
  + print(head);
  +
  + int i,d;
  + cin>>i>>d;
  +
  + /*as we r passing address of first node
  + so no need to return as changes will
  + reflect as we pass by reference
  + */
  +
  + head = insertNode(head,i,d);
  + cout<<endl<<"After insertion : ";
  +
  + print(head);
  +
  + return 0;
  +}
  