整数降順で配置[プログラマ]-Java

問題の説明

せいげんじょうけん

I/O例

私の答え

import java.util.Arrays;

public class Solution {

	public long solution(long n) {
		int length = (int) Math.log10(n) + 1;
		int[] numbers = new int[length];
		
		for(int i = 1; i <= length; i++) {
			numbers[i-1] = (int) (n % (Math.pow(10, i)) / Math.pow(10, i-1));
		}
		Arrays.sort(numbers);
		
		String answer = "";
		for(int i = length - 1; i >= 0; i--) {
			answer += numbers[i];
		}
		
        return Long.parseLong(answer);
    }
}

他人の解答

import java.util.*;

class Solution {
  public long solution(long n) {
        String[] list = String.valueOf(n).split("");
        Arrays.sort(list);

        StringBuilder sb = new StringBuilder();
        for (String aList : list) sb.append(aList);

        return Long.parseLong(sb.reverse().toString());
  }
}