#include <iostream>
using namespace std;

int solve(string s, int score = 0){
	for(int i = 0; i + 2 < s.size(); i++) for(int j = i + 1; j + 1 < s.size(); j++) for(int k = j + 1; k < s.size(); k++) if(s[i] != '0' && s[i] != s[j] && s[j] == s[k]){
		int cww = (s[i] - '0') * 100 + (s[j] - '0') * 10 + (s[k] - '0');
		string tmp = s;
		tmp.erase(tmp.begin() + k);
		tmp.erase(tmp.begin() + j);
		tmp.erase(tmp.begin() + i);
		score = max(score, solve(tmp) + cww);
	}
	return score;
}

int main(){
	string n;
	cin >> n;
	cout << solve(n) << endl;
}