#![allow(non_snake_case)]

use std::cmp;
use std::io::{ self };

fn cww(v: &[char]) -> i64 {
    debug_assert_eq!(3, v.len());
    let v: Vec<_> = v.iter().map(|c| c.to_digit(10).unwrap() as i64).collect();
    if v[0] == 0 { return 0; }
    if v[0] == v[1] { return 0; }
    if v[1] != v[2] { return 0; }
    100*v[0] + 10*v[1] + v[2]
}

fn f(S: &[char]) -> i64 {
    if S.len() < 3 { return 0; }

    let mut res = 0;
    for i in 0..S.len() {
        for j in i+1..S.len() {
            for k in j+1..S.len() {
                let v = [S[i], S[j], S[k]];
                let vcww = cww(&v);
                if vcww == 0 { continue; }
                let t: Vec<_> = (0..S.len())
                    .filter(|&x| x != i && x != j && x != k)
                    .map(|x| S[x])
                    .collect();
                let cur = vcww + f(&t);
                res = cmp::max(res, cur);
            }
        }
    }
    res
}

fn main() {
    let mut S = String::new();
    io::stdin().read_line(&mut S).expect("i/o error");
    let S: Vec<_> = S.trim().chars().collect();

    let ans = f(&S);

    println!("{}", ans);
}