Linked list Insert at nth position C++

//Insert at nth position linked list C++.
//This program inserts every where except the first location i.e. does not insert at head.

Solution:

#include <iostream>

using namespace std;

struct node{

int id;

node *next;

};

void print (node *h);

int main(){

node *head = 0, *tail = 0;

while (1){

int n;

cout << "1. New Entry." << endl;

cout << "2. Print all." << endl;

cin >> n;

if ( n == 1){

cout << "After which ID? "; int id; cin >> id;

node *newPtr = new node;

newPtr -> next = NULL;

//Finding the id.

node *p = head;

while (p!=NULL){

if (p->id == id){

break;

}

p = p->next;

}//If id found the p will point to the node after which we are going to insert.

if (p == NULL)//If id not found.

cout << "ID Not in the linked list.";

if (head == NULL){

head = newPtr;

tail = newPtr;

}

else//If id found the p will point to the node after which we insert.

{//Inserting.

newPtr ->next = p->next;

p->next = newPtr;

}

cout << "\nAssign ID: ";

cin >> newPtr->id;

}

else if(n==2){

print(head);

}

else{

cout << "BY"<< endl;

return 0;

}

}

}

void print (node *h){

while (h!=NULL){

cout << "ID: ";

cout << h->id << endl << endl;

h = h->next;

}

}