class CaseInsensitiveString {
    private String content;
    public CaseInsensitiveString(String string) {
        this.content = string;
    }

    public boolean equals(Object o) {
        if (o instanceof CaseInsensitiveString) {
            CaseInsensitiveString cis = (CaseInsensitiveString)o;
            return content.equalsIgnoreCase(cis.content);
        }
        else if (o instanceof String) {  /* Bad part */
            String s = (String)o;
            return content.equalsIgnoreCase(s);
        }
        else
            return false;
    }
} // class CaseInsensitiveString

public class SymmetryExample {
    public static void main(String[] args) throws SimpleSetFullException {
        CaseInsensitiveString s1 = new CaseInsensitiveString("hej");
        String s2 = "Hej";

        System.out.println("s1.equals(s2): " + (s1.equals(s2))); // true
        System.out.println("s2.equals(s1): " + (s2.equals(s1))); // false!

        SimpleSet set1 = new SimpleSet();
        set1.add(s1);
        System.out.println("set1.contains(s1): " + set1.contains(s1)); // true
        System.out.println("set1.contains(s2): " + set1.contains(s2)); // true

        SimpleSet set2 = new SimpleSet();
        set2.add(s2);
        System.out.println("set2.contains(s2): " + set2.contains(s2)); // true
        System.out.println("set2.contains(s1): " + set2.contains(s1)); // false!
    }
} // class SymmetryExample