题解 | #图片整理#

import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String str=in.next();
        char[] chs=str.toCharArray();
        //Arrays.sort(chs);
        chs=arrayToSort(chs);
        StringBuilder res=new StringBuilder();
        for(char ch:chs){
            res.append(ch);
        }
        System.out.println(res);
    }
    public static char[] arrayToSort(char[] ary){//选择排序
        char temp;
        for(int i=0;i<ary.length-1;i++){
            for(int j=i+1;j<ary.length;j++){
                if(ary[i]>ary[j]){
                    temp=ary[i];
                    ary[i]=ary[j];
                    ary[j]=temp;
                }
            }
        }
        return ary;
    }
}

思路:搞个冒泡或者选择排序就可以了,不建议用api的sort()方法,

算法就是让你算的,不是用巧的,真有本事自己写个Arrays.sort()的底层自己调自己才叫厉害