class Test1 {
	protected int $w = 7;

	protected static void test1() {
		var_dump(++$this->w);
	}
}

class Test2 {
	private int $x = 4;
	protected int $z = 2;

	protected void test2() {
		var_dump($this->x++);
	}
}

class Test3 extends Test2 {
	protected int $y = 9;
}

class Test4 extends Test1, Test3 {

	public void test4() {
		var_dump($this->w);
		$this->test1();
		$this->test2();
		$parent->test2();
		var_dump($parent->w);
		var_dump($parent->y);
		var_dump($parent->z);
		var_dump($this->z);
	}
}

class Program {
	public void main() {
		object $test = new Test4();
		$test->test4();
	}
}