#include <algorithm>
#include <bitset>
#include <cassert>
#include <cctype>
#include <chrono>
#define _USE_MATH_DEFINES
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iostream>
#include <iterator>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
using namespace std;

#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()

const int INF = 0x3f3f3f3f;
const long long LINF = 0x3f3f3f3f3f3f3f3fLL;
const double EPS = 1e-8;
const int MOD = 1000000007; // 998244353;
const int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};
/*-------------------------------------------------*/
bool ok(vector<int> &hand) {
  FOR(i, 1, 8) {
    int waru = hand[i] % 3;
    if (hand[i + 1] < waru || hand[i + 2] < waru) return false;
    hand[i + 1] -= waru;
    hand[i + 2] -= waru;
  }
  return true;
}

int main() {
  cin.tie(0); ios::sync_with_stdio(false);
  // freopen("input.txt", "r", stdin);

  string s; cin >> s;
  vector<int> mahjong(10, 0);
  for (char c : s) ++mahjong[c - '0'];
  FOR(ans, 1, 10) if (mahjong[ans] <= 3) {
    vector<int> now(mahjong);
    ++now[ans];
    int two = 0;
    FOR(i, 1, 10) {
      if (now[i] == 2) ++two;
    }
    if (two == 6) {
      cout << ans << '\n';
      continue;
    }
    FOR(i, 1, 10) if (now[i] >= 2) {
      vector<int> tmp(now);
      tmp[i] -= 2;
      if (ok(tmp)) {
        cout << ans << '\n';
        break;
      }
    }
  }
  return 0;
}