import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        Scanner sc = new Scanner();
        char[] values = sc.next().toCharArray();
        for (int i = 0; i < values.length - 1; i++) {
            char max = '0';
            int idx = 0;
            for (int j = i + 1; j < values.length; j++) {
                if (max <= values[j]) {
                    max = values[j];
                    idx = j;
                }
            }
            if (values[i] < max) {
                char tmp = values[idx];
                values[idx] = values[i];
                values[i] = tmp;
                break;
            }
        }
        System.out.println(values);
    }
}
class Scanner {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringTokenizer st = new StringTokenizer("");
    StringBuilder sb = new StringBuilder();
    
    public Scanner() throws Exception {
        
    }
    
    public int nextInt() throws Exception {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws Exception {
        return Long.parseLong(next());
    }
    
    public double nextDouble() throws Exception {
        return Double.parseDouble(next());
    }
    
    public String next() throws Exception {
        while (!st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }
    
}