public class ShadowTest {

  public int x = 100;

  class FirstLevel {

    public int x = 200;

    String toString(int x) {
       return "x = " + x + "\nthis.x = " + this.x + "\nShadowTest.this.x = " + ShadowTest.this.x;
    }
    
    public String toString() { return "X in FirstLevel is "+x+" and "+ShadowTest.this;}
  }
  
  public String toString() { return "X in ShadowTest is "+x; }

  public static void main(String args[]) {
    ShadowTest st = new ShadowTest();
    ShadowTest.FirstLevel fl = st.new FirstLevel();
    System.out.println(fl.toString(23));    
    System.out.println(st);
    System.out.println(fl);
  }
}