MultiLista problema...accesso

[Mozillaro]

#include<iostream>
using namespace std;

template<class H> class Nodo{
   private:
      H key;
      Nodo<H>* next;
      
   public:
      Nodo(H x) : key(x), next(NULL){
        
      }   
      
      void setKey(H x){
         key = x;
      }
      
      void setNext(Nodo<H>* next){
         this->next = next;
      }
      
      Nodo<H>* getNext(){
         return next;
      }
      
      H getKey(){
         return key;
      }
      
      H* getPtrKey(){
         return &key;   
      }
  
};

template<class H> class List{
   private:
      int n;
      Nodo<H>* head;
  
   public:
      List(){
         head = NULL;
         n = 0;
      }
      
      List<H>* insert(H x){
         Nodo<H>* prev = NULL;
         Nodo<H>* i = head;
        
         while(i != NULL)
         {
            prev = i;
            i = i->getNext();
         }
        
         Nodo<H>* nd = new Nodo<H>(x);
         n++;
        
         if (prev == NULL)
            head = nd;
         else
            prev->setNext(nd);
        
         nd->setNext(i);         
        
         return this;
      }
      
      List<H>* del(H x){
         Nodo<H>* prev = NULL;
         Nodo<H>* i = head;
        
         while(i != NULL && i->getKey() != x )
         {
            prev = i;
            i = i->getNext();
         }
        
         if( i == NULL ) return this;
        
         if( prev == NULL )
            head = head->getNext();
         else
            prev->setNext(i->getNext());
            
         n--;
         return this;
      }

      void _removehead(){
         if( head != NULL ){
            Nodo<H>* succ = head->getNext();
            delete head;
            head = succ;
         }
      }
      
      Nodo<H>* getHead() const{
         return head;
      }
      
      void print(){
         Nodo<H>* tmp = head;
         while( tmp != NULL ){
            cout << tmp->getKey() << " ";
            tmp = tmp->getNext();
         } 
         cout << endl;
      }
      
      friend ostream& operator<<(ostream& stream, const List<H>& l)
      {
         Nodo<H>* tmp = l.getHead();
         while(tmp != NULL){
            stream << tmp->getKey() << " ";
            tmp = tmp->getNext();
         }
        
         return stream;
      }
};

template<class H> class MultiList{
   private:
      List< List<H> >* l;
  
   public:
      MultiList(){
         l = new List< List<H> >();
      }
      
      MultiList<H>* insert(H x){
         Nodo< List<H> >* head = l->getHead();
        
         if(head)
         {
            if( x%2 == 0)
               head->getPtrKey()->insert(x);
            else
            {
               List <H> aux;
               aux.insert(x);
               l->insert(aux);
            }
         }
        
         return this;
      }
      
      void print(){
         Nodo< List<H> >* tmp = l->getHead();
         while(tmp != NULL){
            cout << tmp->getKey() << " ";
            tmp = tmp->getNext();
         }
      }
      

};

int main(){
   List<int>* SingleList = new List<int>();
   SingleList->insert(4)->insert(5)->insert(1)->insert(7)->print();
   SingleList->del(4)->print();
  
   MultiList<int>* DoubleList = new MultiList<int>();
   DoubleList->insert(2)->insert(4)->insert(21)->insert(30)->insert(70)->insert(10);
   DoubleList->print();
  
  
}

ragazzi non riesco a capire com'è possibile che la multilista che ho creato non visualizzi nulla, il fatto è che la head mi risulta null, quando invece nell'insert(credo di aver inserito correttamente i valori)

 

[Mozillaro]

up

 

[Mozillaro]

RISOLTO

 

[Marcus Aseth]

suggerimento: usa nullptr anzichè NULL, inoltre in main manca il delete corrispondente a quel new, dovresti usare smart pointers :)