#include<bits/stdc++.h>
using namespace std;

map<string,int> mp;

int solve(string s){
  if(mp.count(s))return mp[s];

  int res=0;
  for(int i=0;i<(int)s.size();i++){
    if(s[i]=='0')continue;
    for(int j=i+1;j<(int)s.size();j++){
      if(s[j]==s[i])continue;
      for(int k=j+1;k<(int)s.size();k++){
        if(s[j]!=s[k])continue;
        string tmp="";
        for(int l=0;l<(int)s.size();l++)
          if(l!=i&&l!=j&&l!=k)
            tmp+=s[l];

        int num=(s[i]-'0')*100+(s[j]-'0')*10+(s[k]-'0');
        res=max(res,num+solve(tmp));
      }
    }
  }
  
  return mp[s]=res;
}


int main(){
  string N;
  cin>>N;
  cout<<solve(N)<<endl;
  return 0;
}