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    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StreamTokenizer in = new StreamTokenizer(br);

        PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
        in.nextToken();
        int a = (int) in.nval;

        in.nextToken();
        int b = (int) in.nval;

        int start = a / 10000;
        int end = b / 10000;

        int count = 0;

        for (int y = start; y <= end; y++) {
            // 年份转字符串（如2001→"2001"）
            String year = Integer.toString(y);
            // 反转年份得到MMDD
            String revYear = new StringBuilder(year).reverse().toString(); // 2001→"1002"

            // 拆分反转后的字符串为月份、日期（"1002"→month=10，day=02）
            int month = Integer.parseInt(revYear.substring(0, 2));
            int day = Integer.parseInt(revYear.substring(2, 4));

            // 拼接成8位日期
            int date = y * 10000 + month * 100 + day;

            // 日期在[a,b]区间内 并且 日期合法
            if (date >= a && date <= b) {
                if (isValidDate(y, month, day)) {
                    count++; // 符合条件则计数+1
                }
            }
        }
        out.println(count);

        out.flush();
        out.close();
        br.close();
    }

    private static boolean isValidDate(int y, int month, int day) {
        if (month < 1 || month > 12 || day < 1) {
            return false;
        }

        int[] monthDay = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
        if (isLeap(y)) {
            monthDay[2] = 29;
        }

        return day <= monthDay[month];
    }

    private static boolean isLeap(int y) {
        return (y % 4 == 0 && y % 100 != 0) || (y % 400 == 0);
    }