[JAVA/백준] DFS와 BFS: 유기농 배추

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import java.util.Scanner;

/**
 * @author HEESOO
 *
 */
public class Main {
	static int cnt;
	static int m, n;
	static int[][] map;
	static boolean[][] visit;
	public static void dfs(int x, int y) {
		if(visit[x][y]) return;
		
		visit[x][y]=true;
		int[] dotX= {0,0,-1,1};
		int[] dotY= {-1,1,0,0};
		for(int i=0;i<4;i++) {
			int xx=x+dotX[i];
			int yy=y+dotY[i];
			if(0<=xx&&xx<m&&0<=yy&&yy<n)
				if(map[xx][yy]==1&&!visit[xx][yy])
					dfs(xx, yy);
		}
	}
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scan = new Scanner(System.in);
		int t=scan.nextInt();
		for(int tt=0;tt<t;tt++) {
			cnt=0;
			m=scan.nextInt();
			n=scan.nextInt();
			int k=scan.nextInt();
			map=new int[m][n];
			visit=new boolean[m][n];
			for(int i=0;i<k;i++) {
				int x=scan.nextInt();
				int y=scan.nextInt();
				map[x][y]=1;
			}
			
			for(int i=0;i<m;i++) {
				for(int j=0;j<n;j++) {
					if(map[i][j]==1&&!visit[i][j]) {
						cnt++;
						dfs(i, j);
					}
				}
			}
			
			System.out.println(cnt);
		}
		
	}
}