#include <bits/stdc++.h>

using namespace std;
int s(string a){
    int counter = 0;
    for(int i = 0; i < a.size();++i){
        if ((a[i] - '0') % 3 == 0){
            counter++;
        }
    }
    return counter;
}
bool comp(string a, string b){
    int ansa = s(a), ansb = s(b);
    if (ansa == ansb){
        return stoi(a) < stoi(b);
    }else{
        return ansa < ansb;
    }
}

int main()
{
    long long a, b, c;
    cin >> a >> b >> c;
    long long ab = a + b,
              ac = a + c,
              bc = b + c;
    vector <string> vec;
    vec.push_back(to_string(ab));
    vec.push_back(to_string(ac));
    vec.push_back(to_string(bc));
    sort(vec.begin(), vec.end(), comp);
    long long ans = 1;
    string d = vec.back();
    for(auto i : d){
        if ((i - '0') % 3 == 0){
            ans *= i - '0';
        }
    }
    cout << ans;
    return 0;
}