OJ Board

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import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.StringTokenizer;

public class B {

	static int N, M;
	static Set[] sets;

	public static void main(String[] args) throws IOException 
	{
		Scanner sc = new Scanner(System.in);
		PrintWriter out = new PrintWriter(System.out);

		int tc = Integer.parseInt(sc.nextLine());
		while(tc-->0)
		{
			StringTokenizer st = new StringTokenizer(sc.nextLine());
			N = Integer.parseInt(st.nextToken());
			M = Integer.parseInt(st.nextToken());
			sets = new Set[M];

			for(int i = 0; i < M; ++i)
			{
				st = new StringTokenizer(sc.nextLine());
				Set s = new Set();
				while(st.hasMoreTokens())
					s.x.add(Integer.parseInt(st.nextToken()) - 1);
				sets[i] = s;
			}

			boolean possible = false;
			for(long i = 0; !possible && i < 1l<<N; ++i)
			{
				boolean can = true;
				for(Set s: sets)
				{
						if(s.x.size() == 3)
						{
							long sum = ((i>>s.x.get(0))&1) + ((i>>s.x.get(1))&1) + ((i>>s.x.get(2))&1);
							if(sum <= 0 || sum >= 3)
								can = false;
						}
						else
							if(s.x.size() == 2)
							{
								long sum = ((i>>s.x.get(0))&1) + ((i>>s.x.get(1))&1);
								if(sum != 1)
									can = false;
							}
							else
								can = false;
					if(!can)
						break;
				}
				possible |= can;
			}
			System.out.print(possible?'Y':'N');
			if(tc != 0)
				sc.nextLine();
		}

		out.flush();
		out.close();
	}

	static class Set { ArrayList<Integer> x = new ArrayList<Integer>(); }

	static class Scanner 
	{
		StringTokenizer st;
		BufferedReader br;

		public Scanner(InputStream s){	br = new BufferedReader(new InputStreamReader(s));}

		public String next() throws IOException 
		{
			while (st == null || !st.hasMoreTokens()) 
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}

		public int nextInt() throws IOException {return Integer.parseInt(next());}

		public long nextLong() throws IOException {return Long.parseLong(next());}

		public String nextLine() throws IOException {return br.readLine();}

		public double nextDouble() throws IOException { return Double.parseDouble(next()); }

		public boolean ready() throws IOException {return br.ready();}
	}
}