https://programmers.co.kr/learn/courses/30/lessons/12917
import java.util.Arrays;
import java.util.Collections;
class Solution {
public String solution(String s) {
String[] arr = s.split("");
Arrays.sort(arr, Collections.reverseOrder());
return String.join("", arr);
}
}
String[] arr = s.split(""); : String -> String 배열Arrays.sort(arr, Collections.reverseOrder()); : 배열을 역순으로 정렬String.join("", arr); : String 배열 -> String char[] sol = str.toCharArray();
Arrays.sort(sol);
return new StringBuilder(new String(sol)).reverse().toString();
str.toCharArray(); : String -> char 배열Arrays.sort(sol);