As technologies develop, manufacturers are making the process of unlocking a phone as user-friendly as possible. To unlock its new phone, Arkady's pet dog Mu-mu has to bark the password once. The phone represents a password as a string of two lowercase English letters.

Mu-mu's enemy Kashtanka wants to unlock Mu-mu's phone to steal some sensible information, but it can only bark n distinct words, each of which can be represented as a string of two lowercase English letters. Kashtanka wants to bark several words (not necessarily distinct) one after another to pronounce a string containing the password as a substring. Tell if it's possible to unlock the phone in this way, or not.

Input

The first line contains two lowercase English letters — the password on the phone.

The second line contains single integer n (1 ≤ n ≤ 100) — the number of words Kashtanka knows.

The next n lines contain two lowercase English letters each, representing the words Kashtanka knows. The words are guaranteed to be distinct.

Output

Print "YES" if Kashtanka can bark several words in a line forming a string containing the password, and "NO" otherwise.

You can print each letter in arbitrary case (upper or lower).

Examples

Input

ya
4
ah
oy
to
ha


Output

YES


Input

hp
2
ht
tp


Output

NO


Input

ah
1
ha


Output

YES

Note

In the first example the password is "ya", and Kashtanka can bark "oy" and then "ah", and then "ha" to form the string "oyahha" which contains the password. So, the answer is "YES".

In the second example Kashtanka can't produce a string containing password as a substring. Note that it can bark "ht" and then "tp" producing "http", but it doesn't contain the password "hp" as a substring.

In the third example the string "hahahaha" contains "ah" as a substring.
	import java.io.*;
 
 
 
 
import java.math.*;
import java.nio.file.attribute.AclEntry.Builder;
import java.security.KeyStore.Entry;
import java.util.*;
 
 
 
	 
	public  class Khatri {
		private InputStream is;
		private PrintWriter out;
		int time = 0, DP[], start[], end[], dist[],  black[];
		static int MOD = (int)(1e9+7);
		int arr[];
		int weight[][];
		int x[];
		int y[];
		int parent[];
		int MAX = 800000, N, K, L;
		long red[];
		ArrayList<Integer>[] amp;
		HashSet<Integer> hs = new HashSet<>();
		long Dp[][][][] = new long[110][110][12][12];
		public static void main(String[] args) throws Exception 
		{
			new Thread(null, new Runnable() 
			{
			public void run() 
			{
				try {
	 
			//new CODEFORCES().soln();
			} catch (Exception e) 
				{
					System.out.println(e);
				}
			}
		}, "1", 1 << 26).start();
			new Khatri().soln();
		}
		char ch[][]; 
		int n1, n2, k1, k2, M;
		static ArrayList<Integer>[] g;
        static ArrayList<Integer> ar[];
		static long ok[];	 
		static char a[][];
		static int phi[]=new int[500005];
		void solve()
        {
			String s=ns();
			int n=ni();
			int index1=-1;
			int count=0;
			int count1=0;
			int max=0;
			int max1=0;
			String lol[]=new String[n];
			for(int i=0;i<n;i++)
			{
				String p=ns();
				if(p.equals(s))
				{
					out.println("YES");
					return;
				}
				lol[i]=p;
			}
			for(int i=0;i<n;i++)
			{
				for(int j=0;j<n;j++)
				{
					
					if(lol[i].charAt(1)==s.charAt(0)&&lol[j].charAt(0)==s.charAt(1))
					{
						out.println("YES");
					return;
					}
					
				}
			}
			out.print("NO");
        }
				
		
		public static long find(int v,int start,int end,int l,int r)
    	{
    	    if(r < start || end < l)
    	    {
    	    	return Long.MAX_VALUE;
    	    }
    	    if(l <= start && end <= r)
    	    {
    	        return (tre[v]);
    	    }
    	    int mid = (start + end) / 2;
    	    long p1 = find(2*v, start, mid, l, r);
    	    long p2 = find(2*v+1, mid+1, end, l, r);
    	    return Math.min(p1, p2);          
    	}
		static long tre[]=new long[8000005];
		public static void Update(int v,int tl,int tr,int index,long val)
    	{
    		if(tl==tr)
    		{
    			tre[v]=val;
    		}
    		else
    		{
    			int mid=(tl+tr)/2;
    			if(tl <= index &&index <= mid)
    	        {
    	            Update(2*v,tl, mid, index, val);
    	        }
    	        else
    	        {
    	        	Update(2*v+1,mid+1,tr, index, val);
    	        }
    			tre[v]=(Math.min(tre[2*v],tre[2*v+1]));
    		}
    	}
		
			
		
		
		
        
		
		
	    
		
              
       
 
       
       
            boolean isPrime(int x)
            {
            if(x==0||x==1)
            	return false;
			for(int i = 2;i*1L*i<=x;i++) if(x%i==0) return false;
			return true;
		}
	    int  p ;
		void buildGraph(int n)
		{
			for(int i = 0; i<n ;i++){
				int x1 = ni() -1, y1 = ni()-1;
				amp[x1].add(y1);
				amp[y1].add(x1);
				x[i] = x1; y[i] = y1;
			}
		}
		long get(int x){
			long val = 0;
			for(int i = 0; i< N; i++){
				val += Math.abs(x-arr[i]);
				x+=L;
			}
			return val;
		}
		
		long modInverse(long a, long mOD2){
	        return  power(a, mOD2-2, mOD2);
		}
		long power(long x, long y, long m)
		{
			if (y == 0)
	    return 1;
		long p = power(x, y/2, m) % m;
		p = (p * p) % m;
	 
		return (y%2 == 0)? p : (x * p) % m;
		}
		
		public static long gcd(long a, long b){
			if(b==0) return a;
			return gcd(b,a%b);
		}
		
		public static int[] shuffle(int[] a, Random gen){
			for(int i = 0, n = a.length;i < n;i++)
			{ 
				int ind = gen.nextInt(n-i)+i; 
				int d = a[i]; 
				a[i] = a[ind];
				a[ind] = d; 
			} 
		return a; 
		}
		class Pair2 implements Comparable<Pair2>{
			long a;
			long b;
			long c;
			Pair2(long x,long y,long z){
			this.a=x;
			this.b=y;
			this.c=z;
			}
			public int hashCode() {
				return Objects.hash();
			}
			
			@Override
			public int compareTo(Pair2 arg0) {
				return (int)(arg0.b-b);
			}
			
		}
		
		class Pair1 implements Comparable<Pair1>{
			long a;
			long b;
			long c;
			Pair1(long x,long y,long z){
			this.a=x;
			this.b=y;
			this.c=z;
			}
			public int hashCode() {
				return Objects.hash();
			}
			
			@Override
			public int compareTo(Pair1 arg0) {
				return (int)(arg0.c-c);
			}
			
		}
		long power(long x, long y, int mod){
			long ans = 1;
			while(y>0){
				if(y%2==0){
					x = (x*x)%mod;
					y/=2;
				}
				else{
					ans = (x*ans)%mod;
					y--;
				}
			}
			return ans;
		}
		void soln() {
			is = System.in;
			out = new PrintWriter(System.out);
			long s = System.currentTimeMillis();
			solve();
            out.flush();
		}
 		private byte[] inbuf = new byte[1024];
		public int lenbuf = 0, ptrbuf = 0;
	 
		private int readByte() {
			if (lenbuf == -1)
				throw new InputMismatchException();
			if (ptrbuf >= lenbuf) {
				ptrbuf = 0;
				try {
					lenbuf = is.read(inbuf);
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (lenbuf <= 0)
					return -1;
			}
			return inbuf[ptrbuf++];
		}
	 
		private boolean isSpaceChar(int c) {
			return !(c >= 33 && c <= 126);
		}
	 
		private int skip() {
			int b;
			while ((b = readByte()) != -1 && isSpaceChar(b))
				;
			return b;
		}
	 
		private double nd() {
			return Double.parseDouble(ns());
		}
	 
		private char nc() {
			return (char) skip();
		}
		private String ns() {
			int b = skip();
			StringBuilder sb = new StringBuilder();
			while (!(isSpaceChar(b))) { 
				sb.appendCodePoint(b);
				b = readByte();
			}
			return sb.toString();
		}
		private char[] ns(int n) {
			char[] buf = new char[n];
			int b = skip(), p = 0;
			while (p < n && !(isSpaceChar(b))) {
				buf[p++] = (char) b;
				b = readByte();
			}
			return n == p ? buf : Arrays.copyOf(buf, p);
		}
		private int[][] nm(int n, int m) {
			int[][] map = new int[n][m];
			for (int i = 0; i < n; i++)
			{
				for(int j=0;j<m;j++)
					map[i][j]=ni();
			}
			return map;
		}
	 
		private int[] na(int n) {
			int[] a = new int[n];
			for (int i = 0; i < n; i++)
				a[i] = ni();
			return a;
		}
	 
		private int ni() {
			int num = 0, b;
			boolean minus = false;
			while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'))
				;
			if (b == '-') {
				minus = true;
				b = readByte();
			}
	 
			while (true) {
				if (b >= '0' && b <= '9') {
					num = num * 10 + (b - '0');
				} else {
					return minus ? -num : num;
				}
				b = readByte();
			}
		}
	 
		private long nl() {
			long num = 0;
			int b;
			boolean minus = false;
			while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'))
				;
			if (b == '-') {
				minus = true;
				b = readByte();
			}
	 
			while (true) {
				if (b >= '0' && b <= '9') {
					num = num * 10 + (b - '0');
				} else {
					return minus ? -num : num;
				}
				b = readByte();
			}
		}
	 
		private boolean oj = System.getProperty("ONLINE_JUDGE") != null;
	 
		private void tr(Object... o) {
			if (!oj)
				System.out.println(Arrays.deepToString(o));
		}
	} 