hackerrank Day15: Linked List

#include <iostream>
#include <cstddef>
using namespace std;    
class Node
{
    public:
        int data;
        Node *next;
        Node(int d){
            data=d;
            next=NULL;
        }
};
class Solution{
    public:        
         Node* insert(Node *head,int data)
      {
          Node *temp = new Node(data);
          if(head == NULL){
             head = temp;
              return head;
          }
          Node *q, *p;
          p = head;
          q = head -> next;
          
          while(q){
              p = q;
              q = p -> next;
          }
          
          p -> next = temp;
          return head;
      }
          void display(Node *head)
      {
          Node *start=head;
          while(start)
          {
              cout<<start->data<<" ";
              start=start->next;
          }
      }
};
int main()
{
    Node* head=NULL;
      Solution mylist;
    int T,data;
    cin>>T;
    while(T-->0){
        cin>>data;
        head=mylist.insert(head,data);
    }    
    mylist.display(head);
        
}