#include <iostream>
#include <string>

int dfs(const std::string& s) {
    int n = s.length();

    int ret = 0;
    for (int k = 0; k < n; ++k) {
        for (int j = 0; j < k; ++j) {
            for (int i = 0; i < j; ++i) {
                if (s[i] == '0' ||
                    s[i] == s[j] ||
                    s[j] != s[k]) continue;

                int x = (s[i] - '0') * 100 +
                        (s[j] - '0') * 10 +
                        (s[k] - '0') * 1;

                std::string t;
                for (int l = 0; l < n; ++l) {
                    if (l == i || l == j || l == k) continue;
                    t.push_back(s[l]);
                }

                ret = std::max(ret, dfs(t) + x);
            }
        }
    }
    return ret;
}

void solve() {
    std::string s;
    std::cin >> s;

    std::cout << dfs(s) << std::endl;
}

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

    solve();

    return 0;
}