题解 | #字符串排序#

Character 排序 array.sort(Comparator.compareInt(Character::toLowerCase));

import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        while(scan.hasNext()){
            
            String str = scan.nextLine();
            List<Character> list = new ArrayList<>();
            StringBuilder strb = new StringBuilder();
            for(char c : str.toCharArray()){
                if(Character.isLetter(c)){
                    list.add(c);
                }
            }
            list.sort(Comparator.comparingInt(Character::toLowerCase));
            for(int i = 0, j = 0; i<str.length(); i++){
                if(Character.isLetter(str.charAt(i))){
                    strb.append(list.get(j));
                    j++;
                }
                else{
                    strb.append(str.charAt(i));
                }
            }
            System.out.println(strb.toString());
        }
        scan.close();
    }
}