...Once upon a time a man came to the sea. The sea was stormy and dark. The man started to call for the little mermaid to appear but alas, he only woke up Cthulhu...

Whereas on the other end of the world Pentagon is actively collecting information trying to predict the monster's behavior and preparing the secret super weapon. Due to high seismic activity and poor weather conditions the satellites haven't yet been able to make clear shots of the monster. The analysis of the first shot resulted in an undirected graph with n vertices and m edges. Now the world's best minds are about to determine whether this graph can be regarded as Cthulhu or not.

To add simplicity, let's suppose that Cthulhu looks from the space like some spherical body with tentacles attached to it. Formally, we shall regard as Cthulhu such an undirected graph that can be represented as a set of three or more rooted trees, whose roots are connected by a simple cycle.

It is guaranteed that the graph contains no multiple edges and self-loops.

<image>

Input

The first line contains two integers — the number of vertices n and the number of edges m of the graph (1 ≤ n ≤ 100, 0 ≤ m ≤ <image>).

Each of the following m lines contains a pair of integers x and y, that show that an edge exists between vertices x and y (1 ≤ x, y ≤ n, x ≠ y). For each pair of vertices there will be at most one edge between them, no edge connects a vertex to itself.

Output

Print "NO", if the graph is not Cthulhu and "FHTAGN!" if it is.

Examples

Input

6 6
6 3
6 4
5 1
2 5
1 4
5 4


Output

FHTAGN!

Input

6 5
5 6
4 6
3 1
5 1
1 2


Output

NO

Note

Let us denote as a simple cycle a set of v vertices that can be numbered so that the edges will only exist between vertices number 1 and 2, 2 and 3, ..., v - 1 and v, v and 1.

A tree is a connected undirected graph consisting of n vertices and n - 1 edges (n > 0).

A rooted tree is a tree where one vertex is selected to be the root.
import java.util.*;
import java.io.*;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.math.MathContext;

import static java.lang.Math.*;
import static java.util.Arrays.*;
import static java.util.Collections.*;



/*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ CONTROLLER CLASS   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
/*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/


public class Main {
	public static void main(String[] args) throws Exception {
		InputReader in = new InputReader(System.in);
		PrintWriter out = new PrintWriter(System.out);
		TaskA solver = new TaskA();
		solver.solve(1, in, out);
		out.close();
	}

static class TaskA {
	

	
/*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ OTHER USEFULL METHODS ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
/*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
		// GCD && LCM
		long gcd(long a, long b) {
			return b == 0 ? a : gcd(b, a % b);
		}

		long lcm(long a, long b) {
			return a * (b / gcd(a, b));
		}

		// REverse a String
		String rev(String s) {
			return new StringBuilder(s).reverse().toString();
		}
        
/*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ SOLUTION  IS RIGHT HERE^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
/*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
	
	
		public void solve(int testNumber, InputReader in, PrintWriter out) throws IOException {
			// BufferedReader br = new BufferedReader(new
			// InputStreamReader(System.in));
			// Scanner sc = new Scanner(System.in);
			
			//final long mod = (long)1e9+7;
			int n = in.nextInt() , m = in.nextInt();
			dsu u = new dsu(n);
			for(int i = 0; i < m; i++)
				u.union(in.nextInt(), in.nextInt());
			if(u.cnt() == 1 && n == m)
				out.println("FHTAGN!");
			else out.println("NO");
		}
	}

/*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
/*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ OTHER USEFULL CLASSES ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
/*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
//union
static class dsu{
	 int[] union , size;
	 int count; 
	 public dsu(int n){
		 count = n;
		 union = new int[n+1];
		 size = new int[n+1];
		 for(int i = 0; i <= n; i++){
			 union[i] = i;
			 size[i] = 1;
		 }
	 }
	 public int root(int s){
		 while(s != union[s])
			 s = union[s];
		 return s;
	 }
	 
	 public boolean connected(int a , int b){
	    return root(a) == root(b);
	 }
	 
	 public void union(int a, int b){
		 int ea = root(a);
		 int eb = root(b);
		 if(ea == eb);
		 else if(size[ea] > size[eb]){
			 union[eb] = ea;
			 size[ea] += size[eb];
			 count--;
		 }else{
			union[ea] = eb;
			size[eb] += size[ea];
			count--;
		 }
		 //System.out.println(count);
	 }
	 public int cnt(){
		 //System.out.println(count);
		 return count;
	 }
	 
}


 /*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
 /*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ INPUT READER CLASS ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
 /*``````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````*/
	


    static class InputReader {
		private byte[] buf = new byte[8000];
		private int index;
		private int total;
		private InputStream in;
		//BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		public InputReader(InputStream stream) {
			in = stream;
		}

		public int scan() {
			if (total == -1)
				throw new InputMismatchException();
			if (index >= total) {
				index = 0;
				try {
					total = in.read(buf);
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (total <= 0)
					return -1;
			}
			return buf[index++];
		}

		public long scanlong() {
			long integer = 0;
			int n = scan();
			while (isWhiteSpace(n))
				n = scan();
			int neg = 1;
			if (n == '-') {
				neg = -1;
				n = scan();
			}
			while (!isWhiteSpace(n)) {
				if (n >= '0' && n <= '9') {
					integer *= 10;
					integer += n - '0';
					n = scan();
				} else
					throw new InputMismatchException();
			}
			return neg * integer;
		}

		private int scanInt() {
			int integer = 0;
			int n = scan();
			while (isWhiteSpace(n))
				n = scan();
			int neg = 1;
			if (n == '-') {
				neg = -1;
				n = scan();
			}
			while (!isWhiteSpace(n)) {
				if (n >= '0' && n <= '9') {
					integer *= 10;
					integer += n - '0';
					n = scan();
				} else
					throw new InputMismatchException();
			}
			return neg * integer;
		}

		public double scandouble() {
			double doubll = 0;
			int n = scan();
			int neg = 1;
			while (isWhiteSpace(n))
				n = scan();
			if (n == '-') {
				neg = -1;
				n = scan();
			}
			while (!isWhiteSpace(n) && n != '.') {
				if (n >= '0' && n <= '9') {
					doubll *= 10;
					doubll += n - '0';
					n = scan();
				}
			}
			if (n == '.') {
				n = scan();
				double temp = 1;
				while (!isWhiteSpace(n)) {
					if (n >= '0' && n <= '9') {
						temp /= 10;
						doubll += (n - '0') * temp;
						n = scan();
					}
				}
			}
			return neg * doubll;
		}

		private float scanfloat() {
			float doubll = 0;
			int n = scan();
			int neg = 1;
			while (isWhiteSpace(n))
				n = scan();
			if (n == '-') {
				neg = -1;
				n = scan();
			}
			while (!isWhiteSpace(n) && n != '.') {
				if (n >= '0' && n <= '9') {
					doubll *= 10;
					doubll += n - '0';
					n = scan();
				}
			}
			if (n == '.') {
				n = scan();
				double temp = 1;
				while (!isWhiteSpace(n)) {
					if (n >= '0' && n <= '9') {
						temp /= 10;
						doubll += (n - '0') * temp;
						n = scan();
					}
				}
			}
			return neg * doubll;
		}

		public String scanstring() {
			StringBuilder sb = new StringBuilder();
			int n = scan();
			while (isWhiteSpace(n))
				n = scan();
			while (!isWhiteSpace(n)) {
				sb.append((char) n);
				n = scan();
			}
			return sb.toString();
		}

		public String scan_nextLine() {
			int n = scan();
			while (isWhiteSpace(n))
				n = scan();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(n);
				n = scan();
			} while (!isEndOfLine(n));
			return res.toString();
		}

		public boolean isWhiteSpace(int n) {
			if (n == ' ' || n == '\n' || n == '\r' || n == '\t' || n == -1)
				return true;
			return false;
		}

		private boolean isEndOfLine(int c) {
			return c == '\n' || c == '\r' || c == -1;
		}
		/// Input module

		public int nextInt() {
			return scanInt();
		}

		public long nextLong() {
			return scanlong();
		}

		public double nextDouble() {
			return scandouble();
		}

		public float nextFloat() {
			return scanfloat();
		}

		public String next() {
			return scanstring();
		}

		public String nextLine() throws IOException {
			return scan_nextLine();
		}

		public int[] readIntArray(int size) {
			int[] array = new int[size];
			for (int i = 0; i < size; i++) {
				array[i] = nextInt();
			}
			return array;
		}
	}
 
}