#include<bits/stdc++.h>
using lint=long long;
void cmx(lint&x,lint y){if(x<y)x=y;}
int main(){
    std::cin.tie(nullptr);std::ios_base::sync_with_stdio(false);
    std::cout.setf(std::ios_base::fixed);std::cout.precision(15);
    lint n;std::cin>>n;
    std::vector<lint>a;
    for(;n;n/=10)a.push_back(n%10);
    std::reverse(a.begin(),a.end());
    n=a.size();
    lint N=1ll<<n;
    std::vector<lint>dp(N);
    for(lint i=0;i<N;i++){
        if(__builtin_popcountll(i)%3!=0)continue;
        for(lint j=0;j<n;j++){
            for(lint k=j+1;k<n;k++){
                for(lint l=k+1;l<n;l++){
                    if(!(i>>j&1)||!(i>>k&1)||!(i>>l&1)
                        ||a.at(j)==a.at(k)||a.at(k)!=a.at(l))continue;
                    cmx(dp.at(i),
                        dp.at(i^1<<j^1<<k^1<<l)
                        +a.at(j)*100+a.at(k)*10+a.at(l));
                }
            }
        }
    }
    std::cout<<*std::max_element(dp.begin(),dp.end())<<'\n';
}