Screen.h

#ifndef SCREEN_H
#define SCREEN_H

#include <string>
#include <cstddef>

class Screen {
public:
	typedef std::string::size_type pos;
	Screen() = default;
	Screen(pos ht, pos wd) : height(ht), width(wd), contents(ht * wd, ' ') {}
	Screen(pos ht, pos wd, char c) : height(ht), width(wd), contents(ht * wd, c) {}

	char get() const { return contents[cursor]; }
	inline char get(pos ht, pos wd) const;
	Screen &move(pos r, pos c);
	void some_member() const;
private:
	pos cursor = 0;
	pos height = 0, width = 0;
	std::string contents;

	mutable std::size_t access_ctr;
};

inline Screen &Screen::move(pos r, pos c) {
	pos row = r * width;
	cursor = row + c;
	return *this;
}

char Screen::get(pos r, pos c) const {
	pos row = r * width;
	return contents[row + c];
}

void Screen::some_member() const {
	++access_ctr;
}

#endif