2019 카카오 겨울 인턴 튜플 [Java]

import java.util.*;
class Solution {
    public int[] solution(String s) {
        int[] arr;
        int idx=0;
        Set<String> set=new HashSet<>();
        
        String[] str=s.replaceAll("[{]"," ")
                .replaceAll("[}]"," ")
                .trim()
                .split(" , ");
        arr = new int[str.length];
        
        Arrays.sort(str,(a,b)->{return a.length()-b.length();});
        for(String s1:str){
            for(String s2:s1.split(",")){
                if(set.add(s2)){
                    arr[idx++]=Integer.valueOf(s2);
                }
            }
        }
        return arr;
    }
}