use std::{
    fs::File,
    io::{BufRead, BufReader},
    iter,
};

fn main() -> () {
    let path = "input.txt";

    let input = File::open(path).unwrap();
    let buf = BufReader::new(input);

    let mut top = [0; 3];
    let mut cur = 0;

    for line in buf.lines().chain(iter::once(Ok(String::from("")))) {
        let line = line.unwrap();
        if line == "" {
            top[0] = top[0].max(cur);
            top.sort();
            cur = 0;
        } else {
            cur += line.parse::<i32>().unwrap();
        }
    }

    println!("{}", top.iter().fold(0, |acc, el| { acc + el }));
}