[SWEA][D2] 1954. 달팽이 숫자 Java

import java.util.Scanner;  
  
public class snailQuiz {  
    public static void main(String[] args) {  
  
  
        Scanner sc = new Scanner(System.in);  
        int T;  
        T=sc.nextInt();  
  
  
  
        for(int test_case = 1; test_case <= T; test_case++)  
        {  
            int N = sc.nextInt();  
            int[][] snailArray = new int[N][N];  
  
            int[] dx = { 0, 1, 0, -1 };  
            int[] dy = { 1, 0, -1, 0 };  //우,하,좌,상  
            int d = 0; // 회전인덱스  
  
  
  
            // 좌표  
            int xIndex = 0;  
            int yIndex = 0;  
  
  
            for (int i = 1; i <= N*N ; i++) {  
                snailArray[xIndex][yIndex] = i;  
                int nx = xIndex + dx[d];  
                int ny = yIndex + dy[d];  
  
                if (nx < 0 || nx >= N || ny < 0 || ny >= N || snailArray[nx][ny] != 0){  
                    d = (d + 1) % 4;  //방향바꿈  
                    nx = xIndex + dx[d];  
                    ny = yIndex + dy[d];  
                }  
                xIndex = nx;  
                yIndex = ny;  
            }  
  
            System.out.printf("#%d\n",test_case);  
            for (int r = 0; r < N; r++) {  
                for (int c = 0; c < N; c++)  
                    System.out.print(snailArray[r][c] + " ");  
                System.out.println();  
            }  
        }  
    }  
}

방향에 대한 방향성을 조금더 잘 생각해야되는 부분이었다.
1. 반복되는 구조 확인하기
2. 배열일 경우 배열의 dx dy로 방향으로 하여 문제푸는 방법 찾기