hackerrank-time-conversion.java

static String timeConversion(String s) {
        String t = s.substring(0, 2);
        String p = s.substring(s.length() - 2, s.length());
        if(p.equals("AM")) {
            if(t.equals("12")) t = "00";
        } else {
            if(!t.equals("12")) t = Integer.toString(Integer.parseInt(t) + 12);
        }

        return t + s.substring(2, s.length()-2);

    }