class Abbreviations {
    static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream("days_of_week.txt"), "utf-8"))
        List<String> readAllLines = br.readLines()

        for (int i = 0; i < readAllLines.size(); i++) {
            String line = readAllLines.get(i)
            if (line.length() == 0) continue

            String[] days = line.split(" ")
            if (days.length != 7) throw new RuntimeException("There aren't 7 days on line " + (i + 1))

            Map<String, Integer> temp = new HashMap<>()
            for (String day : days) {
                Integer count = temp.getOrDefault(day, 0)
                temp.put(day, count + 1)
            }
            if (temp.size() < 7) {
                System.out.print(" ∞  ")
                System.out.println(line)
                continue
            }

            int len = 1
            while (true) {
                temp.clear()
                for (String day : days) {
                    String sd
                    if (len >= day.length()) {
                        sd = day
                    } else {
                        sd = day.substring(0, len)
                    }
                    Integer count = temp.getOrDefault(sd, 0)
                    temp.put(sd, count + 1)
                }
                if (temp.size() == 7) {
                    System.out.printf("%2d  %s\n", len, line)
                    break
                }
                len++
            }
        }
    }
}