백준) 7569_토마토2

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

7569번: 토마토

 

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.LinkedList;
import java.util.Queue;
import java.util.StringTokenizer;
 
public class Main {
    
    static class Node {
        int x;
        int y;
        int h;
        int z;
        
        Node (int x, int y, int h, int z) {
            this.x = x;
            this.y = y;
            this.h = h;
            this.z = z;
        }
    }
    static int count = 0;
    static int max = 0;
    static int N, M, H;
    static int[][][] map;
    static boolean[][][] visited;
    static Queue<Node> q = new LinkedList<>(); 
    static int[] dxy = {1, 0, 0, -1, 0, 0, 1, 0};
    
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine());
        M = Integer.parseInt(st.nextToken());
        N = Integer.parseInt(st.nextToken());
        H = Integer.parseInt(st.nextToken());
        
        map = new int[N][M][H];
        visited = new boolean[N][M][H];
        
        count = N * M * H;
        for (int i = 0; i < H; i++) {
            for (int j = 0; j < N; j++) {
                st = new StringTokenizer(br.readLine());
                for (int k = 0; k < M; k++) {
                    map[j][k][i] = Integer.parseInt(st.nextToken());
                    if (map[j][k][i] == 1) {
                        q.offer(new Node(j, k, i, 0));
                        visited[j][k][i] = true;
                    }
                    if (map[j][k][i] == 1 || map[j][k][i] == -1) {
                        count--;
                    }
                }
            }
        }
        bfs();
        if (count == 0) {
            System.out.println(max);
            return;
        }
        System.out.println(-1);
    }
    static void bfs() {
        while(!q.isEmpty()) {
            Node cur = q.poll();
            
            max = Math.max(max, cur.z);
            
            for (int i = 0; i < 6; i++) {
                int nx = cur.x + dxy[i];
                int ny = cur.y + dxy[i + 1];
                int nh = cur.h + dxy[i + 2];
                
                if (nx < 0 | ny < 0 | nh < 0 | nx >= N | ny >= M | nh >= H) continue;
                
                if(!visited[nx][ny][nh] && map[nx][ny][nh] == 0) {
                    visited[nx][ny][nh] = true;
                    q.offer(new Node(nx, ny, nh, cur.z + 1));
                    count--;
                }
            }
        }
    }
}