BOJ7569_토마토

https://www.acmicpc.net/problem/7569

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.LinkedList;
import java.util.Queue;
import java.util.StringTokenizer;
/**
 * 2차원 토마토랑 다 똑같지만
 * 3차원 배열 사용시 for문 사용 주의
 * z->x->y
 */
public class Main {
 
    static Queue<Integer> q = new LinkedList<>();
    static int[] dx = { 1, 0, 0, -1, 0, 0 };
    static int[] dy = { 0, 0, 1, 0, 0, -1 };
    static int[] dh = { 0, -1, 0, 0, 1, 0 };
    static int cnt;
 
    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
 
        StringTokenizer st = new StringTokenizer(br.readLine().trim(), " ");
        int C = Integer.parseInt(st.nextToken());
        int R = Integer.parseInt(st.nextToken());
        int H = Integer.parseInt(st.nextToken());
        int[][][] map = new int[R][C][H];
 
        int zero_cnt = 0;
        for (int k = 0; k < H; k++) {
            for (int i = 0; i < R; i++) {
                StringTokenizer st2 = new StringTokenizer(br.readLine().trim(), " ");
                for (int j = 0; j < C; j++) {
                    int number = Integer.parseInt(st2.nextToken());
                    if (number == 0) {
                        zero_cnt++;
                    }
                    map[i][j][k] = number;
                }
            }
        }
 
        if (zero_cnt == 0) {
            System.out.println(0);
            return;
        }
 
        for (int k = 0; k < H; k++) {
            for (int i = 0; i < R; i++) {
                for (int j = 0; j < C; j++) {
                    if (map[i][j][k] == 1) {
                        q.add(k);
                        q.add(i);
                        q.add(j);
                    }
                }
            }
        }
 
        cnt = -1;
        bfs(map, C, R, H);
 
        for (int k = 0; k < H; k++) {
            for (int i = 0; i < R; i++) {
                for (int j = 0; j < C; j++) {
                    if (map[i][j][k] == 0) {
                        System.out.println(-1);
                        return;
                    }
                }
            }
        }
        System.out.println(cnt);
 
    } // end of main
 
    private static void bfs(int[][][] map, int y, int x, int z) {
 
        while (!q.isEmpty()) {
            cnt++;
            int q_size = q.size() / 3;
            for (int i = 0; i < q_size; i++) { // 큐에 (0,0,0)이게 한개니깐 /3
                int tomato_z = q.poll();
                int tomato_x = q.poll(); // 한턴에 뺀 토마토x,y,z 좌표
                int tomato_y = q.poll();
                for (int k = 0; k < 6; k++) {
                    int nz = tomato_z + dh[k];
                    int nx = tomato_x + dx[k];
                    int ny = tomato_y + dy[k];
                    if (nx >= 0 && nx < x && ny >= 0 && ny < y && nz >= 0 && nz < z && map[nx][ny][nz] == 0) {
                        map[nx][ny][nz] = 1;
                        q.add(nz);
                        q.add(nx);
                        q.add(ny);
                    }
                }
            }
        } // end of q while
    } // end of bfs
} // end of class