#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
using namespace std;
typedef pair<int,int> P;
int memo[1LL<<12];

int main(){
    int64_t N;
    int L=0;
    cin>>N;
    int a[12];
    while(N){
        a[L++]=N%10;
        N/=10;
    }
    int ans=0;
    vector<int> V3,V6,V9;
    if(L>=3){
        int comb=(1<<3)-1;
        int ans=0;
        while(comb<(1<<L)){
            int CWW[3],cww=0;
            for(int i=0;i<L;i++){
                if(comb&(1<<i))CWW[cww++]=a[i];
            }
            if(CWW[0]==CWW[1]&&CWW[1]!=CWW[2]&&CWW[2]){
                memo[comb]=CWW[2]*100+CWW[1]*10+CWW[0];
                ans=max(ans,memo[comb]);
                V3.push_back(comb);
            }
            int x = comb&-comb, y=comb+x;
            comb=((comb&~y)/x>>1)|y;
        }
    }
    if(L>=6){
        for(int i=0;i<V3.size();i++){
            for(int j=i+1;j<V3.size();j++){
                if(V3[i]&V3[j]) continue;
                int sum=memo[V3[i]]+memo[V3[j]];
                memo[V3[i]|V3[j]]=max(memo[V3[i]|V3[j]],sum);
                V6.push_back(V3[i]|V3[j]);
                ans=max(ans,sum);
            }
        }
    }
    if(L>=9){
        for(auto v3:V3){
            for(auto v6:V6){
                if(v3&v6) continue;
                int sum=memo[v3]+memo[v6];
                memo[v3|v6]=max(memo[v3|v6],sum);
                V9.push_back(v3|v6);
                ans=max(sum,ans);
            }
        }
    }
    if(L==12){
        for(auto v3:V3){
            for(auto v9:V9){
                if(v3&v9)continue;
                int sum=memo[v3]+memo[v9];
                memo[v3|v9]=max(memo[v3|v9],sum);
                ans=max(sum,ans);
            }
        }
    }
    cout<<ans<<endl;
    return 0;
}