[프로그래머스/Java] 문자열 정렬하기 (1)

-Code

import java.util.*;

class Solution {
    public int[] solution(String my_string) {
        ArrayList<Integer> answer = new ArrayList<>();

        for (char c : my_string.toCharArray()) {
            if (Character.isDigit(c)) answer.add(c - '0');
        }
        answer.sort(Comparator.naturalOrder());
                
        return answer.stream().mapToInt(Integer::intValue).toArray();
    }
}