text: #ifndef TEXTDISPLAY_H
  #define TEXTDISPLAY_H
  #include <iostream>
  #include <vector>
  #include "observer.h"
  #include "state.h"
  #include "info.h"
  class Cell;
  
  class TextDisplay: public Observer<Info, State> {
    std::vector<std::vector<char>> theDisplay;
    const int gridSize;
   public:
    TextDisplay(int n);
  
    void notify(Subject<Info, State> &whoNotified) override;
  
    friend std::ostream &operator<<(std::ostream &out, const TextDisplay &td);
  };
  #endif
  
  