#include <iostream>
using namespace std;
 
class A {
protected:
	int &_y = _x[0];
	int _x[2];
public:
	void setX(int x) {
		_x[0] = x;
	}
	int getX() {
		return _x[0];
	}
	void setY(int y) {
		_y = y;
	}
	int getY() {
		return _y;
	}
};
 
int main() {
	A a;
	a.setY(0);
	a.setX(5);
	cout << "x = " << a.getX() << endl;
	cout << "y = " << a.getY() << endl;
	cout << endl;
 
	a.setY(7);
	cout << "x = " << a.getX() << endl;
	cout << "y = " << a.getY() << endl;
 
	// your code goes here
	return 0;
}

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