题解 | #记票统计#哎，要是真有这么简单就好了

import java.util.*;
import java.io.*;
public class Main{
    public static void main(String[] args) throws Exception{
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        PrintWriter out=new PrintWriter(new OutputStreamWriter(System.out));
        String str=br.readLine();
        char[] ch=str.toCharArray();
        Arrays.sort(ch);
        String res=new String(ch);
        out.println(res);
        out.flush();
        
    }
}