구름톤 챌린지 13일차

문제

https://level.goorm.io/exam/195695/%EB%B0%9C%EC%A0%84%EA%B8%B0-2/quiz/1

구름LEVEL

 

코드

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

class Main {
	static int building [] = new int [33];
	
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st = new StringTokenizer(br.readLine());
		
		int n = Integer.parseInt(st.nextToken());
		int k = Integer.parseInt(st.nextToken());
		
		int board [][] = new int [1000][1000];
		
		for(int i=0;i<n;i++){
			st = new StringTokenizer(br.readLine());
			for(int j=0;j<n;j++){
				board[i][j] = Integer.parseInt(st.nextToken());
			}
		}
		
		bfs(n, k, board);
		
		int max = 0;
		int idx = 0;
		for(int i=0;i<31;i++){
			if(max <= building[i]) {
				max = building[i];
				idx = i;
			}
		}
		
		System.out.println(idx);
	}
	
	static void bfs(int n, int k, int board[][]){
		int dx [] = {0, 1, 0, -1};
		int dy [] = {1, 0, -1, 0};
		boolean visited [][] = new boolean [1000][1000];
		Queue<int []> que = new LinkedList<>();
		
		for(int i=0;i<n;i++){
			for(int j=0;j<n;j++){
				if(visited[i][j]) continue;
				
				que.add(new int [] {i, j});
				visited[i][j] = true;
				int cnt = 1;
				int brd = board[i][j];
				
				while(!que.isEmpty()){
					int [] point = que.poll();
					
					for(int t=0;t<4;t++){
						int nx = point[0] + dx[t];
						int ny = point[1] + dy[t];
						
						if(nx < 0 || ny < 0 || nx >= n || ny >= n) continue;
						if( visited[nx][ny] || board[i][j] != board[nx][ny] ) continue;
						
						visited[nx][ny] = true;
						que.add(new int [] {nx, ny});
						cnt++;
					}
				}
				if(cnt >= k) building[brd]++;
			}
		}
	}
}