题解 | #图片整理#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String str = in.nextLine();
        char[] charList = new char[str.length()];
        for(int i = 0 ;i<str.length();i++){
            charList[i] = str.charAt(i);
        }
        for(int i = 0;i<charList.length;i++){
            for(int j = i+1;j<charList.length;j++){
                if(charList[i]>charList[j]){
                    char flag = charList[i];
                    charList[i] = charList[j];
                    charList[j] = flag;
                }
            }
        }
        for(int i =0;i<charList.length;i++){
            System.out.print(charList[i]);
        }      
    }
}