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.File;import java.io.FileInputStream;import java.io.FileNotFoundException;
import java.io.IOException;import java.io.PrintStream;import java.io.PrintWriter;
import java.security.AccessControlException;import java.util.Arrays;import java.util.Collection;
import java.util.Comparator;import java.util.List;import java.util.Map;import java.util.Objects;
import java.util.Scanner;import java.util.TreeMap;import java.util.TreeSet;import java.util.function.Function;
import java.util.stream.Collectors;import java.util.stream.IntStream;import java.util.stream.LongStream;
import java.util.stream.Stream;public class _p000868A {static public void main(final String[] args) 
throws IOException{p000868A._main(args);}
static private class p000868A extends Solver{public p000868A(){nameIn="in/900/p000868A.in"
;singleTest=true;}@Override public void solve()throws IOException{String p=sc.nextLine
().trim();int n=sc.nextInt();if(sc.hasNextLine()){sc.nextLine();}String[]s=new String
[n];for(int _is=0;_is<n;_is++){s[_is]=sc.nextLine().trim();}boolean res=false;TreeSet
<String>first=new TreeSet<>();TreeSet<String>second=new TreeSet<>();for(int i=0;
i<n;i++){if(p.equals(s[i])){res=true;break;}first.add(s[i].substring(0,1));second
.add(s[i].substring(1));}if(!res){res=second.contains(p.substring(0,1))&& first.
contains(p.substring(1));}pw.println(res?"YES":"NO");}static public void _main(String
[]args)throws IOException{new p000868A().run();}}static private class Pair<K,V>{
private K k;private V v;public Pair(final K t,final V u){this.k=t;this.v=u;}public
 K getKey(){return k;}public V getValue(){return v;}}static private abstract class
 Solver{protected String nameIn=null;protected String nameOut=null;protected boolean
 singleTest=false;protected boolean preprocessDebug=false;protected boolean doNotPreprocess
=false;protected PrintStream debugPrintStream=null;protected Scanner sc=null;protected
 PrintWriter pw=null;final static String SPACE=" ";final static String SPACES="\\s+"
;private void process()throws IOException{if(!singleTest){int t=lineToIntArray()
[0];while(t-->0){solve();}}else{solve();}}abstract protected void solve()throws 
IOException;protected String[]lineToArray()throws IOException{return sc.nextLine
().trim().split(SPACES);}protected int[]lineToIntArray()throws IOException{return
 Arrays.stream(lineToArray()).mapToInt(Integer::valueOf).toArray();}protected long
[]lineToLongArray()throws IOException{return Arrays.stream(lineToArray()).mapToLong
(Long::valueOf).toArray();}protected void run()throws IOException{boolean done=false
;try{if(nameIn!=null && new File(nameIn).exists()){try(FileInputStream fis=new FileInputStream
(nameIn);PrintWriter pw0=select_output();){done=true;sc=new Scanner(fis);pw=pw0;
process();}}}catch(IOException ex){}catch(AccessControlException ex){}if(!done){
try(PrintWriter pw0=select_output();){sc=new Scanner(System.in);pw=pw0;process()
;}}}private PrintWriter select_output()throws FileNotFoundException{if(nameOut!=
null){return new PrintWriter(nameOut);}return new PrintWriter(System.out);}public
 static Map<Integer,List<Integer>>mapi(final int[]a){return IntStream.range(0,a.
length).collect(()->new TreeMap<Integer,List<Integer>>(),(res,i)->{if(!res.containsKey
(a[i])){res.put(a[i],Stream.of(i).collect(Collectors.toList()));}else{res.get(a[
i]).add(i);}},Map::putAll);}public static Map<Long,List<Integer>>mapi(final long
[]a){return IntStream.range(0,a.length).collect(()->new TreeMap<Long,List<Integer
>>(),(res,i)->{if(!res.containsKey(a[i])){res.put(a[i],Stream.of(i).collect(Collectors
.toList()));}else{res.get(a[i]).add(i);}},Map::putAll);}public static<T>Map<T,List
<Integer>>mapi(final T[]a){return IntStream.range(0,a.length).collect(()->new TreeMap
<T,List<Integer>>(),(res,i)->{if(!res.containsKey(a[i])){res.put(a[i],Stream.of(
i).collect(Collectors.toList()));}else{res.get(a[i]).add(i);}},Map::putAll);}public
 static<T>Map<T,List<Integer>>mapi(final T[]a,Comparator<T>cmp){return IntStream
.range(0,a.length).collect(()->new TreeMap<T,List<Integer>>(cmp),(res,i)->{if(!res
.containsKey(a[i])){res.put(a[i],Stream.of(i).collect(Collectors.toList()));}else
{res.get(a[i]).add(i);}},Map::putAll);}public static Map<Integer,List<Integer>>mapi
(final IntStream a){int[]i=new int[]{0};return a.collect(()->new TreeMap<Integer
,List<Integer>>(),(res,v)->{if(!res.containsKey(v)){res.put(v,Stream.of(i[0]).collect
(Collectors.toList()));}else{res.get(v).add(i[0]);}i[0]++;},Map::putAll);}public
 static Map<Long,List<Integer>>mapi(final LongStream a){int[]i=new int[]{0};return
 a.collect(()->new TreeMap<Long,List<Integer>>(),(res,v)->{if(!res.containsKey(v
)){res.put(v,Stream.of(i[0]).collect(Collectors.toList()));}else{res.get(v).add(
i[0]);}i[0]++;},Map::putAll);}public static<T>Map<T,List<Integer>>mapi(final Stream
<T>a,Comparator<T>cmp){int[]i=new int[]{0};return a.collect(()->new TreeMap<T,List
<Integer>>(cmp),(res,v)->{if(!res.containsKey(v)){res.put(v,Stream.of(i[0]).collect
(Collectors.toList()));}else{res.get(v).add(i[0]);}},Map::putAll);}public static
<T>Map<T,List<Integer>>mapi(final Stream<T>a){int[]i=new int[]{0};return a.collect
(()->new TreeMap<T,List<Integer>>(),(res,v)->{if(!res.containsKey(v)){res.put(v,
Stream.of(i[0]).collect(Collectors.toList()));}else{res.get(v).add(i[0]);}},Map::
putAll);}public static List<int[]>listi(final int[]a){return IntStream.range(0,a
.length).mapToObj(i->new int[]{a[i],i}).collect(Collectors.toList());}public static
 List<long[]>listi(final long[]a){return IntStream.range(0,a.length).mapToObj(i->
new long[]{a[i],i}).collect(Collectors.toList());}public static<T>List<Pair<T,Integer
>>listi(final T[]a){return IntStream.range(0,a.length).mapToObj(i->new Pair<T,Integer
>(a[i],i)).collect(Collectors.toList());}public static List<int[]>listi(final IntStream
 a){int[]i=new int[]{0};return a.mapToObj(v->new int[]{v,i[0]++}).collect(Collectors
.toList());}public static List<long[]>listi(final LongStream a){int[]i=new int[]
{0};return a.mapToObj(v->new long[]{v,i[0]++}).collect(Collectors.toList());}public
 static<T>List<Pair<T,Integer>>listi(final Stream<T>a){int[]i=new int[]{0};return
 a.map(v->new Pair<T,Integer>(v,i[0]++)).collect(Collectors.toList());}public static
 String join(final int[]a){return Arrays.stream(a).mapToObj(Integer::toString).collect
(Collectors.joining(SPACE));}public static String join(final long[]a){return Arrays
.stream(a).mapToObj(Long::toString).collect(Collectors.joining(SPACE));}public static
<T>String join(final T[]a){return Arrays.stream(a).map(v->Objects.toString(v)).collect
(Collectors.joining(SPACE));}public static<T>String join(final T[]a,final Function
<T,String>toString){return Arrays.stream(a).map(v->toString.apply(v)).collect(Collectors
.joining(SPACE));}public static<T>String join(final Collection<T>a){return a.stream
().map(v->Objects.toString(v)).collect(Collectors.joining(SPACE));}public static
<T>String join(final Collection<T>a,final Function<T,String>toString){return a.stream
().map(v->toString.apply(v)).collect(Collectors.joining(SPACE));}public static<T
>String join(final Stream<T>a){return a.map(v->Objects.toString(v)).collect(Collectors
.joining(SPACE));}public static<T>String join(final Stream<T>a,final Function<T,
String>toString){return a.map(v->toString.apply(v)).collect(Collectors.joining(SPACE
));}public static<T>String join(final IntStream a){return a.mapToObj(Integer::toString
).collect(Collectors.joining(SPACE));}public static<T>String join(final LongStream
 a){return a.mapToObj(Long::toString).collect(Collectors.joining(SPACE));}public
 static List<Integer>list(final int[]a){return Arrays.stream(a).mapToObj(Integer
::valueOf).collect(Collectors.toList());}public static List<Integer>list(final IntStream
 a){return a.mapToObj(Integer::valueOf).collect(Collectors.toList());}public static
 List<Long>list(final long[]a){return Arrays.stream(a).mapToObj(Long::valueOf).collect
(Collectors.toList());}public static List<Long>list(final LongStream a){return a
.mapToObj(Long::valueOf).collect(Collectors.toList());}public static<T>List<T>list
(final Stream<T>a){return a.collect(Collectors.toList());}public static<T>List<T
>list(final T[]a){return Arrays.stream(a).collect(Collectors.toList());}}}
