#include <string>
using namespace std;

struct listNode
{
  string data;
  listNode *next;
};

class LinkedList
{
  private: 
   listNode *head;

  public:
   LinkedList(): head(0){}       // default constructor
   ~LinkedList();                // destructor
   void shift();                 // delete the first element from the list
   void inFront(string &s);      // insert a new element to the head
   void inBack(string &s);       // insert a new element to the tail
   void printForw();             // print out the list elements
};