private static int solve(String s) {
        if (s == null || s.length() == 0)
            return 0;
        if (s.length() == 1)
            return Integer.parseInt(s);
        int sum = 0;
        for (int i = 1; i < s.length(); i++) {
            if (s.charAt(i - 1) == s.charAt(i))
                sum += (s.charAt(i) - '0');
        }
        if (s.charAt(s.length() - 1) == s.charAt(0))
            sum += (s.charAt(0) - '0');

        return sum;
    }
Why Did you create this class? what does it do?
src/adventofcode/Captcha_1.java