[알고리즘문제풀기] 배열 회전시키기

문제

내가 작성한 정답

import java.util.stream.*;
class Solution {
    public int[] solution(int[] numbers, String direction) {
        int len = numbers.length;
        return IntStream.range(0,len)
                .map(i -> numbers[(i+(direction.startsWith("r")?-1:1)+len)%len])
                .toArray();
    }
}



import java.util.stream.*;
class Solution {
    public int[] solution(int[] numbers, String direction) {
        int len = numbers.length;
        boolean right = direction.equals("right");
        return IntStream.range(0,len)
                .map(i->{
                    if(right) return i == 0 ? numbers[len-1] : numbers[i-1];
                    else return  i == len-1 ? numbers[0] : numbers[i+1];
                })
                .toArray();
    }
}



class Solution {
    public int[] solution(int[] numbers, String direction) {
        int len = numbers.length;
        int[] answer = new int[len];
        if(direction.startsWith("r")){
            answer[0] = numbers[len-1];
            for(int i=1; i<len; i++){
                answer[i] = numbers[i-1];
            }
        } else {
            answer[len-1] = numbers[0];
            for(int i=0; i<len-1; i++){
                answer[i] = numbers[i+1];
            }
        }
        return answer;
    }
}

다른 사람들의 정답

import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

class Solution {
    public int[] solution(int[] numbers, String direction) {
        List<Integer> list = Arrays.stream(numbers).boxed().collect(Collectors.toList());

        if (direction.equals("right")) {
            list.add(0, list.get(list.size() - 1));
            list.remove(list.size() - 1);
        } else {
            list.add(list.size(), list.get(0));
            list.remove(0);
        }
        return list.stream().mapToInt(Integer::intValue).toArray();
    }
}