[JAVA] 백준 2667 단지번호붙이기

import java.util.*;

public class Main {

static int N;

static int[][] map = new int[25][25];

static boolean[][] visit = new boolean[25][25];

static int[] dx = {0,1,0,-1};

static int[] dy = {1,0,-1,0};

static int cnt = 1;

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

N = sc.nextInt();

for(int i=0;i<N;i++){

String str = sc.next();

for(int j=0;j<str.length();j++){

map[i][j] = str.charAt(j)-'0';

}

}

for(int i=0;i<N;i++){

for(int j=0;j<N;j++){

if(map[i][j]==1 && visit[i][j]==false){

bfs(i,j);

cnt++;

}

}

}

System.out.println(cnt-1);

int[] sort = new int[cnt];

for(int i=0;i<N;i++){

for(int j=0;j<N;j++){

if(map[i][j]!=0)

sort[map[i][j]]++;

}

}

Arrays.sort(sort);

for(int i=1;i<cnt;i++){

System.out.println(sort[i]);

}

}

public static void bfs(int x, int y){

Queue<Integer> qx = new LinkedList<Integer>();

Queue<Integer> qy = new LinkedList<Integer>();

qx.offer(x);

qy.offer(y);

while(!qx.isEmpty() && !qy.isEmpty()){

x = qx.poll();

y = qy.poll();

visit[x][y] = true;

map[x][y] = cnt;

for(int i=0;i<4;i++){

int nx = x + dx[i];

int ny = y + dy[i];

if(nx>=0 && ny>=0 && nx<N && ny<N){

if(map[nx][ny]==1 && visit[nx][ny]==false){

qx.offer(nx);

qy.offer(ny);

visit[nx][ny]=true;

}

}

}

}

}

}