[BOJ] 16948 데스 나이트 (JAVA)

https://www.acmicpc.net/problem/16948

16948번: 데스 나이트

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.LinkedList;
import java.util.Queue;
import java.util.StringTokenizer;

public class Main {
	
    public static void main(String[] args) throws Exception {

        int[] dr = { -2, -2,  0,  0,  2,  2 };
        int[] dc = { -1,  1, -2,  2, -1,  1 };
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int N = Integer.parseInt(br.readLine());
        int[][] visited = new int[N][N];
        StringTokenizer st = new StringTokenizer(br.readLine(), " ");
        int r1 = Integer.parseInt(st.nextToken());
        int c1 = Integer.parseInt(st.nextToken());
        int r2 = Integer.parseInt(st.nextToken());
        int c2 = Integer.parseInt(st.nextToken());

        Queue<int[]> q = new LinkedList<>();
        visited[r1][c1] = 1;
        q.offer(new int[] { r1, c1 });

        while (!q.isEmpty()) {
            int[] now = q.poll();

            if (now[0] == r2 && now[1] == c2) {
                System.out.print(visited[now[0]][now[1]] - 1);
                return;
            }

            for (int dir = 0; dir < 6; dir++) {
                int nr = now[0] + dr[dir];
                int nc = now[1] + dc[dir];
                if (0 <= nr && nr < N && 0 <= nc && nc < N && visited[nr][nc] == 0) {
                    q.offer(new int[] { nr, nc });
                    visited[nr][nc] = visited[now[0]][now[1]] + 1;
                }
            }
        }

        System.out.print(-1);

    }
	
}