import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        sc.close();
        Set<Long> set = new HashSet<>();
        for (int k = 0; k <= s.length(); k++) {
            String pre;
            String post;
            int start = 0;
            if (k == 0) {
                pre = "";
                post = s;
                start = 1;
            } else if (k == s.length()) {
                pre = s;
                post = "";
            } else {
                pre = s.substring(0, k);
                post = s.substring(k);
            }
            for (int i = start; i <= 9; i++) {
                String numString = pre + i + post;
                set.add(Long.parseLong(numString));
            }
        }
        System.out.println(set.size());
    }
}