身份证第18位计算

    String[] idDict = {"1", "0", "X", "9", "8", "7", "6", "5", "4", "3", "2"};
    // 17位如下
    String idCard = "53010219200508011";
    List<Integer> nums = new ArrayList<Integer>();
    Matcher m = Pattern.compile("\\d").matcher(idCard);
    while (m.find()) {
      nums.add(Integer.valueOf(m.group()));
    }
    int gg = 7 * nums.get(0) + 9 * nums.get(1) + 10 * nums.get(2)
        + 5 * nums.get(3) + 8 * nums.get(4) + 4 * nums.get(5) + 2 * nums.get(6)
        + 1 * nums.get(7) + 6 * nums.get(8) + 3 * nums.get(9) + 7 * nums.get(10)
        + 9 * nums.get(11) + 10 * nums.get(12) + 5 * nums.get(13) + 8 * nums.get(14)
        + 4 * nums.get(15) + 2 * nums.get(16);
    int eighteen = gg % 11;
    System.out.println(idDict[eighteen]);