Passing a single class instance to another class

Projects Programming
17

My impression is that the intent was for the Puzzle and Box to share a single Debug. My code above tries to use the Debug copy constructor. I think the better way to do that is to have Box keep a pointer to the Debug and have the constructor initialize that pointer:
Box.h

#ifndef BOX_H
#define BOX_H

#include "Debug.h"

class Box {
  private:
    Debug * _debug;
    
  public:
    Box(Debug &debug);
    void begin();
};

#endif

Box.cpp

#include "Box.h"
#include <Arduino.h>

Box::Box(Debug &debug) : _debug(&debug)
{
}

void Box::begin()
{  
  pinMode(28, INPUT_PULLUP);
}