fn main() {
    let mut buf = String::new();
    std::io::stdin().read_line(&mut buf).unwrap();
    
    let mut n: Vec<String> = buf.trim()
        .chars()
        .map(|n| n.to_string())
        .collect();
        
    for i in 0..n.len() {
        let mut max_idx = i;
        for j in i+1..n.len() {
            if n[max_idx] <= n[j] {
                max_idx = j;
            }
        }
        if n[max_idx] != n[i] {
            n.swap(i, max_idx);
            break;
        }
    }
    
    println!("{}", n.concat());
}