#include<bits/stdc++.h>
#define int long long
using namespace std;
string s;
signed main(){
//	freopen("abb.in","r",stdin);
//	freopen("abb.out","w",stdout);
	cin>>s;
	int len=s.size();
	vector<int>dp(1<<len);
	for(int i=0;i<len;i++){
		for(int j=i+1;j<len;j++){
			for(int k=j+1;k<len;k++){
				int c=s[i]-'0',w=s[j]-'0';
				if(c==0||c==w||w!=s[k]-'0')continue;
				dp[(1<<i)|(1<<j)|(1<<k)]=c*100+w*11;
			}
		}
	}
	for(int i=1;i<(1<<len);i++)
		for(int S=i&(i-1);S>0;S=(S-1)&i)dp[i]=max(dp[i],dp[i^S]+dp[S]);
	printf("%lld\n",dp.back());
	return 0;
}