class Forekomster {
    public static void main(String[] args) {
        String str = "kattkukatt";
        System.out.println(antallSubStringer(str, "katt"));
        System.out.println(antallSubStringer(str, "ku"));
        System.out.println(antallSubStringer(str, "hund"));

    }

    public static int antallSubStringer(String str, String sub) {
        if (str.length() < sub.length()) {
            return 0;
        }

        if ( str.substring(0, sub.length()).equals(sub) ) {
            return 1 + antallSubStringer(str.substring(1, str.length()), sub);
        }
        return antallSubStringer(str.substring(1, str.length()), sub);
    }
}