use std::io::Read;
use std::cmp::Reverse;
use std::collections::HashMap;

fn solve(x: &str) {
    let mut x_list: Vec<char> = x.chars().collect();
    x_list.sort_by_key(|&x| Reverse(x));

    let mut char2count: HashMap<char, usize> = HashMap::new();
    let mut min_key: u8 = 9;

    x_list.iter().for_each(|x| {
        min_key = std::cmp::min(min_key, x.to_string().parse::<u8>().unwrap());
        match char2count.get_mut(x) {
            Some(count) => *count += 1,
            None => { char2count.insert(*x, 1); },
        }
    });

    let min_key_char = &(std::char::from_digit(min_key as u32, 10).unwrap());
    let change_idx: usize = x_list.len() - char2count.get(min_key_char).unwrap();
    if x_list[0] == '0' || char2count.len() == 1 {
        println!("{}", -1);
    } else if min_key == 0 && change_idx == 1 {
        println!("{}", -1);
    } else {
        x_list.swap(change_idx - 1, change_idx);
        println!("{}", x_list.iter().map(|c| c.to_string()).collect::<Vec<String>>().join(""));
    }
}

fn main() {
    let mut x = String::new();
    std::io::stdin().read_to_string(&mut x).ok();
    let x = x.trim().split('\n').next().unwrap().trim();
    solve(x);
}