#include <bits/stdc++.h>

using namespace std;

int main(){
    ifstream input_file("input.txt");
    string line;

    int max_energy = 0;

    // if(input_file.is_open()){
    //     int cur_energy = 0;

    //     while(getline(input_file, line)){
    //         if(line.length() > 1){
    //             cur_energy += stoi(line); 
    //         } else{
    //             max_energy = max(cur_energy, max_energy);
    //             cur_energy = 0;
    //         };
    //     }
    // }


    if(input_file.is_open()){
        int energy_max = 0, energy_mid = 0, energy_low = 0;
        int cur_energy = 0;

        while(getline(input_file, line)){
            if(line.length() > 1){
                cur_energy += stoi(line);
            } else{
                if(cur_energy > energy_max){
                    energy_low = energy_mid;
                    energy_mid = energy_max;
                    energy_max = cur_energy;
                } else if(cur_energy > energy_mid){
                    energy_low = energy_mid;
                    energy_mid = cur_energy;
                } else if(cur_energy > energy_low){
                    energy_low = cur_energy;
                }
                cur_energy = 0;
            }
        }

        max_energy = energy_max + energy_mid + energy_low;
    }
    

    cout << "Max. energy: " << max_energy << endl;

    return 0;
}