#ifndef NIMM_H
#define NIMM_H

typedef enum {PLAYER1, PLAYER2} player;
class Nim {
   public:
      // constructors
      Nim();
      Nim(int initial_size);

      // accessors
      bool finished() const;
         // returns true iff all sticks have been taken
      int size_of_heap() const;
         // returns current state of the game (number of sticks)
      player winner() const;
         // PRE: finished() is true
      player next_player() const;
         // PRE: finished() is false
         // returns who has to move next
         // (i.e. to remove sticks from the heap)

      bool valid(int move) const;
         // PRE: finished() is false
         // returns true iff this is a valid move

      // mutators
      void perform_move(int move);
         // PRE: finished() is false and valid(move) is true

   private:
      player other_player() const;
         // returns the other player in respect to whose_turn
      int heap_size; // current state of the game
      player whose_turn; // which player has to move next
};

#endif