#include<algorithm>
#include<complex>
#include<ctype.h>
#include<iomanip>
#include<iostream>
#include<fstream>
#include<map>
#include<math.h>
#include<numeric>
#include<queue>
#include<set>
#include<stack>
#include<stdio.h>
#include<string>
#include<string>
#include<vector>

using namespace std;
typedef long long ll;

#define FOR(i,a,b) for(ll i=(a);i<(b);++i)
#define ALL(v) (v).begin(), (v).end()
#define p(s) cout<<(s)<<endl
#define p2(s, t) cout << (s) << " " << (t) << endl
#define br() p("")
#define pn(s) cout << (#s) << " " << (s) << endl
#define p_yes() p("Yes")
#define p_no() p("No")

const ll mod = 1e9 + 7;
const ll inf = 1e18;

string s;
ll L;

bool is_chihuahua(ll i, ll j, ll k){
    if(s[i]!='0' && s[i]!=s[j] && s[j]==s[k]) return true;
    return false;
}

ll calc_score(ll i, ll j, ll k){
    stringstream ss;
    ss << s[i] << s[j] << s[k];
    return stoi(ss.str());
}
    
ll dfs(ll f){
    ll max_score = 0;
    FOR(i, 0, L){
        FOR(j, i+1, L){
            FOR(k, j+1, L){
                // もう使用済み
                if(f>>i & 1 || f>>j & 1 || f>>k & 1) continue;

                // チワワじゃない
                if(!is_chihuahua(i, j, k)) continue;

                // 今回のフラグ
                ll flag = (1<<i) + (1<<j) + (1<<k);

                // 今回のスコア
                ll score = calc_score(i, j, k);

                max_score = max(max_score, dfs(f+flag) + score);
            }
        }
    }

    return max_score;
}

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

    // input
    cin >> s;
    L = s.size();

    ll ans = dfs(0);
    p(ans);
    
    return 0;
}