FormatPhone

class Ideone {

    static String formatPhone(String s) {
        s = s.replaceAll(" ", "").replaceAll("-", "");
        char[] array = s.toCharArray();
        StringBuilder sb = new StringBuilder();
        boolean shouldThree = array.length % 3 == 0;
        for (int i = 0, j = 0; i < array.length; i++) {
            if (i == array.length - 2 && !shouldThree) {
                if (sb.charAt(sb.length() - 1) != '-') {
                    sb.append("-");
                }
                sb.append(array[i]);
                continue;
            }
            sb.append(array[i]);
            j++;
            if (j % 3 == 0) {
                sb.append("-");
                j = 0;
            }
        }
        if (sb.charAt(sb.length() - 1) == '-') {
            sb.deleteCharAt(sb.length() - 1);
        }
        return sb.toString();
    }

    public static void main(String[] args) throws java.lang.Exception {
        // your code goes here
        String answer = formatPhone("1111222212121212121212");
        System.out.println(answer);
        answer = formatPhone("123");
        System.out.println(answer);
        answer = formatPhone("1234");
        System.out.println(answer);

        answer = formatPhone("12345");
        System.out.println(answer);

        answer = formatPhone("1234567");
        System.out.println(answer);

        answer = formatPhone("111122221212121212121");
        System.out.println(answer);
        answer = formatPhone("11112222121212121212");
        System.out.println(answer);
        answer = formatPhone("111122221212121212");
        System.out.println(answer);

    }

}