题解 | #字符串排序#

import java.util.*;


// 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 input = in.nextLine();
        char[] datas = input.toCharArray();
        for (int i = 0; i < datas.length ; i++) {
            int currentIndex = 0;
            for (int j = 1 ; j < datas.length - i ; j++) {
                if (Character.isLetter(datas[j])) {
                    if (Character.toLowerCase(datas[j]) < Character.toLowerCase(
                                datas[currentIndex])) {
                        int temp = datas[currentIndex];
                        datas[currentIndex] = datas[j];
                        datas[j] = (char) temp;
                    }
                    currentIndex = j;
                }
            }
        }
        System.out.println(new String(datas));
    }
}