content: package v105;
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.PrintWriter;
  import java.util.Stack;
  import java.util.StringTokenizer;
  
  
  public class WakingUpBrain_UVa10507 {
  	
  	public static void main(String[] args) throws IOException 
  	{
  		Scanner sc = new Scanner(System.in);
  		PrintWriter out = new PrintWriter(System.out);
  	
  		while(sc.ready())
  		{
  			int N = sc.nextInt(), M = sc.nextInt();
  			boolean[][] adjMat = new boolean[26][26];
  			int[] wakeUp = new int[26];
  			for(char c: sc.next().toCharArray())
  				wakeUp[c-'A'] = 2;
  			while(M-->0)
  			{
  				char[] e = sc.next().toCharArray();
  				int u = e[0] - 'A', v = e[1] - 'A';
  				adjMat[u][v] = adjMat[v][u] = true;
  				wakeUp[u] |= 1;
  				wakeUp[v] |= 1;
  			}
  			
  			int W = 3, ans = 0;
  			Stack<Integer> stack = new Stack<Integer>();
  			while(W != N)
  			{
  				for(int i = 0; i < 26; ++i)
  					if(wakeUp[i] == 1)
  					{
  						int supp = 0;
  						for(int j = 0; j < 26; ++j)
  							if(adjMat[i][j] && (wakeUp[j] & 2) != 0)
  								++supp;
  						if(supp >= 3)
  							stack.push(i);
  					}
  				if(stack.isEmpty())
  					break;
  				W += stack.size();
  				while(!stack.isEmpty())
  					wakeUp[stack.pop()] |= 2;
  				++ans;
  			}
  			
  			if(W != N)
  				out.println("THIS BRAIN NEVER WAKES UP");
  			else
  				out.printf("WAKE UP IN, %d, YEARS\n", ans);
  		}
  		out.flush();
  		out.close();
  	}
  
  	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
  		{
  			String x = next();
  			StringBuilder sb = new StringBuilder("0");
  			double res = 0, f = 1;
  			boolean dec = false, neg = false;
  			int start = 0;
  			if(x.charAt(0) == '-')
  			{
  				neg = true;
  				start++;
  			}
  			for(int i = start; i < x.length(); i++)
  				if(x.charAt(i) == '.')
  				{
  					res = Long.parseLong(sb.toString());
  					sb = new StringBuilder("0");
  					dec = true;
  				}
  				else
  				{
  					sb.append(x.charAt(i));
  					if(dec)
  						f *= 10;
  				}
  			res += Long.parseLong(sb.toString()) / f;
  			return res * (neg?-1:1);
  		}
  
  		public boolean ready() throws IOException {return br.ready();}
  		
  		public boolean nextEmpty() throws IOException
  		{
  			String s = br.readLine();
  			st = new StringTokenizer(s);
  			return s.isEmpty();
  		}
  
  
  	}
  }