use std::io;

fn main() -> io::Result<()> {
    // read from stdin
    let stdin = io::stdin();
    let lines = stdin.lines();

    let mut elves = Vec::new();
    let mut c_sum = 0;
    for line in lines {
        let content = line.unwrap();
        if content.is_empty() {
            elves.push(c_sum);
            c_sum = 0;
        } else {
            let new_val = match content.parse::<i32>() {
                Ok(v) => v,
                Err(_e) =>{ println!("Error parsing input");  0 }
            };
            c_sum += new_val;
        }
    }
    
    elves.sort();
    elves.reverse();
    let mut result = 0;
    if elves.len() > 3 {
        for n in 0..3 {
            result += elves[n];
        }
        println!("{}", result);
    } else {
        println!("Not enough elves");
    }
    Ok(())
}