

Input

The input consists of a single string of uppercase letters A-Z. The length of the string is between 1 and 10 characters, inclusive.

Output

Output "YES" or "NO".

Examples

Input


GENIUS


Output


YES


Input


DOCTOR


Output


NO


Input


IRENE


Output


YES


Input


MARY


Output


NO


Input


SMARTPHONE


Output


NO


Input


REVOLVER


Output


YES


Input


HOLMES


Output


NO


Input


WATSON


Output


YES
import java.io.*;
import java.util.*;

public class Main2{
	static void main() throws Exception{
		char[]in=sc.nextLine().toCharArray();
		for(int i=0;i+2<in.length;i++) {
			int x=in[i]-'A',y=in[i+1]-'A';
			char nxt=(char)('A'+((x+y)%26));
			if(nxt!=in[i+2]) {
				pw.println("NO");
				return;
			}
		}
		pw.println("YES");
    }
    public static void main(String[] args) throws Exception{
    	sc=new MScanner(System.in);
    	pw = new PrintWriter(System.out);
    	
        int tc=1;
//        tc=sc.nextInt();
        for(int i=1;i<=tc;i++) {
//            pw.printf("Case %d:\n", i);
            main();
        }
        pw.flush();
    }
    static PrintWriter pw;
    static MScanner sc;
    static class MScanner {
        StringTokenizer st;
        BufferedReader br;
        public MScanner(InputStream system) {
            br = new BufferedReader(new InputStreamReader(system));
        }
     
        public MScanner(String file) throws Exception {
            br = new BufferedReader(new FileReader(file));
        }
     
        public String next() throws IOException {
            while (st == null || !st.hasMoreTokens())
                st = new StringTokenizer(br.readLine());
            return st.nextToken();
        }
        public int[] intArr(int n) throws IOException {
            int[]in=new int[n];for(int i=0;i<n;i++)in[i]=nextInt();
            return in;
        }
        public long[] longArr(int n) throws IOException {
            long[]in=new long[n];for(int i=0;i<n;i++)in[i]=nextLong();
            return in;
        }
        public int[] intSortedArr(int n) throws IOException {
            int[]in=new int[n];for(int i=0;i<n;i++)in[i]=nextInt();
            shuffle(in);
            Arrays.sort(in);
            return in;
        }
        public long[] longSortedArr(int n) throws IOException {
            long[]in=new long[n];for(int i=0;i<n;i++)in[i]=nextLong();
            shuffle(in);
            Arrays.sort(in);
            return in;
        }
        public Integer[] IntegerArr(int n) throws IOException {
            Integer[]in=new Integer[n];for(int i=0;i<n;i++)in[i]=nextInt();
            return in;
        }
        public Long[] LongArr(int n) throws IOException {
            Long[]in=new Long[n];for(int i=0;i<n;i++)in[i]=nextLong();
            return in;
        }
        public String nextLine() throws IOException {
            return br.readLine();
        }
     
        public int nextInt() throws IOException {
            return Integer.parseInt(next());
        }
     
        public double nextDouble() throws IOException {
            return Double.parseDouble(next());
        }
     
        public char nextChar() throws IOException {
            return next().charAt(0);
        }
     
        public long nextLong() throws IOException {
            return Long.parseLong(next());
        }
     
        public boolean ready() throws IOException {
            return br.ready();
        }
     
        public void waitForInput() throws InterruptedException {
            Thread.sleep(3000);
        }
        
    }
    static void shuffle(int[]in) {
        for(int i=0;i<in.length;i++) {
            int idx=(int)(Math.random()*in.length);
            int tmp=in[i];
            in[i]=in[idx];
            in[idx]=tmp;
        }
    }
    static void shuffle(long[]in) {
        for(int i=0;i<in.length;i++) {
            int idx=(int)(Math.random()*in.length);
            long tmp=in[i];
            in[i]=in[idx];
            in[idx]=tmp;
        }
    }
}