백준 14716번 - 현수막

 

▶코드

import java.util.*;
import java.io.*;

public class Main {
    static int range[][];
    static boolean visited[][];
    static int dx[] = {0, 0, -1, 1, -1, -1, 1, 1};
    static int dy[] = {-1, 1, 0, 0, -1, 1, -1, 1};
    static int N, M, cnt;
    static LinkedList<Integer> result;

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st;
        st = new StringTokenizer(br.readLine());
        N = Integer.parseInt(st.nextToken());
        M = Integer.parseInt(st.nextToken());
        range = new int[N][M];
        visited = new boolean[N][M];
        result = new LinkedList<>();
        cnt = 1;
        for (int i = 0; i < N; i++) {
            st = new StringTokenizer(br.readLine());
            for (int j = 0; j < M; j++) {
                range[i][j] = Integer.parseInt(st.nextToken());
            }
        }
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < M; j++) {
                if (!visited[i][j] && range[i][j] == 1) {
                    dfs(i, j);
                    result.add(cnt);
                    cnt = 1;
                }
            }
        }
        System.out.println(result.size());
    }
    public static void dfs(int x, int y) {
        visited[x][y] = true;
        for (int i = 0; i < 8; i++) {
            int nx = dx[i] + x;
            int ny = dy[i] + y;
            if (nx >= 0 && ny >= 0 && nx < N && ny < M && !visited[nx][ny] && range[nx][ny] == 1) {
                dfs(nx, ny);
                cnt++;
            }
        }
    }
}