题解 | #图片整理#

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        String str=scanner.nextLine();
        String[] strs=str.split("");
        List<String> lists=new ArrayList<>();
        for(String s:strs)
        {
            lists.add(s);
        }
//        Collections.sort(lists, new Comparator<String>() {
//            @Override
//            public int compare(String o1, String o2) {
//                return o1.charAt(0)-o2.charAt(0);
//            }
//        });
        Collections.sort(lists);
        StringBuffer stringBuffer=new StringBuffer();
        for(String s:lists)
        {
            stringBuffer.append(s);
        }
        System.out.println(stringBuffer.toString());
    }
}