Untitled

#include<bits/stdc++.h> 
 using namespace std ;  
  class node{
    public :  
     int m ; 
      int n ;  
       node* next ; 
        node(int m, int n ){
            this->m = m ;  
             this-> n = n ;  
             this-> next = NULL ;  
            
        }
  };  

   void print_linlist (node* &head){
      node* tmp = head ;  
      while (tmp != NULL){
        cout << tmp->m << " " << tmp->n << "->" ; 
        tmp = tmp->next ;  
      }
   } 
     void input_node(node* &head, node* &tail, int m, int n){
        node* newnode = new node(m,n); 
        if(head == NULL){
            head = newnode ;
            tail = newnode ;  
            return ;
        }
        tail->next = newnode ;  
        tail= tail->next ;  
     } 

     int main (){
        node* head = NULL ; 
        node* tail = NULL ;  
         int m, n ;  
         while(true){
            cin >> m >> n ; 
            if(n == -1 || m== -1){
                break ; 

            }
            input_node(head, tail, m,n);  
         }
         print_linlist(head);  
          }