#include <bits/stdc++.h>

using namespace std;

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

const double PI = acos(-1);

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  string s;
  cin >> s;

  int l = s.length();
  int m = 1<<l;
  vector<int> dp(m);
  for (int mask = 0; mask < m; mask++) {
    for (int i = 0; i < l; i++) {
      for (int j = i+1; j < l; j++) {
        for (int k = j+1; k < l; k++) {
          if ((mask & 1<<i) && (mask & 1<<j) && (mask & 1<<k) && s[i] != '0' && s[j] != s[i] && s[k] == s[j]) {
            string t = string(1, s[i]) + s[j] + s[k];
            int nask = mask;
            nask &= ~(1<<i);
            nask &= ~(1<<j);
            nask &= ~(1<<k);
            dp[mask] = max(dp[mask], dp[nask] + stoi(t));
          }
        }
      }
    }
  }

  cout << dp[m-1] << endl;
  
  return 0;
}