

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.math.*;
import java.util.*;

/*
author : Multi-Thread
*/

public class B {

	static int INF = (int) 1e9 + 7;
	static int MAX = Integer.MAX_VALUE;
	static int MIN = Integer.MIN_VALUE;

	public static void main(String[] args) {

//		int test = fs.nextInt();
		int test = 1;

		for (int cases = 0; cases < test; cases++) {

//			solve();
			System.out.println(solve());

		}
	}

	static String solve() {
		char ar[] = fs.next().toCharArray();
		if (ar.length <= 2)
			return "YES";
		int code = ar[0] - 'A' + 1;
		int code2 = ar[1] - 'A' + 1;
		for (int i = 2; i < ar.length; i++) {
			int code3 = ar[i] - 'A' + 1;
			int nc = code + code2 - 1;
			if (nc > 26) {
				nc %= 26;
			}
//			System.out.println(code + " " + code2 + " " + code3 + " " + nc);
			if (nc != code3)
				return "NO";
			code = code2;
			code2 = code3;
		}
		return "YES";
	}

	static int _min(int... ar) {
		intSort(ar, true);
		return ar[ar.length - 1];
	}

	static int _max(int... ar) {
		intSort(ar, true);
		return ar[ar.length - 1];
	}

	static void intSort(int[] a, boolean reverse) {
		ArrayList<Integer> al = new ArrayList<Integer>();
		for (int i : a)
			al.add(i);
		Collections.sort(al);
		if (reverse) {
			for (int i = 0; i < a.length; i++)
				a[i] = al.get(a.length - i - 1);
		} else {
			for (int i = 0; i < a.length; i++)
				a[i] = al.get(i);
		}
	}

	static void longSort(long[] a, boolean reverse) {
		ArrayList<Long> al = new ArrayList<>();
		for (long i : a)
			al.add(i);
		Collections.sort(al);
		if (reverse) {
			for (int i = 0; i < a.length; i++)
				a[i] = al.get(a.length - i - 1);
		} else {
			for (int i = 0; i < a.length; i++)
				a[i] = al.get(i);
		}
	}

	public static int[] radixSort(int[] f) {
		return radixSort(f, f.length);
	}

	public static int[] radixSort(int[] f, int n) {
		int[] to = new int[n];
		{
			int[] b = new int[65537];
			for (int i = 0; i < n; i++)
				b[1 + (f[i] & 0xffff)]++;
			for (int i = 1; i <= 65536; i++)
				b[i] += b[i - 1];
			for (int i = 0; i < n; i++)
				to[b[f[i] & 0xffff]++] = f[i];
			int[] d = f;
			f = to;
			to = d;
		}
		{
			int[] b = new int[65537];
			for (int i = 0; i < n; i++)
				b[1 + (f[i] >>> 16)]++;
			for (int i = 1; i <= 65536; i++)
				b[i] += b[i - 1];
			for (int i = 0; i < n; i++)
				to[b[f[i] >>> 16]++] = f[i];
			int[] d = f;
			f = to;
			to = d;
		}
		return f;
	}

	static class Pair {
		int first, second;

		public Pair(int first, int second) {
			this.first = first;
			this.second = second;
		}

		public String toString() {
			return "[" + first + "," + second + "]";
		}
	}

	static class LongPair {
		long first;
		long second;

		LongPair(long a, long b) {
			this.first = a;
			this.second = b;
		}

		public String toString() {
			return "[" + first + "," + second + "]";
		}
	}

	static boolean isPrime(long n) {
		// Corner cases
		if (n <= 1)
			return false;
		if (n <= 3)
			return true;
		if (n % 2 == 0 || n % 3 == 0)
			return false;

		long sq = (long) Math.sqrt(n);
		for (int i = 5; i <= sq; i = i + 6)
			if (n % i == 0 || n % (i + 2) == 0)
				return false;

		return true;
	}

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}

	static class OutputWriter {
		private final PrintWriter writer;

		public OutputWriter(OutputStream outputStream) {
			writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
		}

		public OutputWriter(Writer writer) {
			this.writer = new PrintWriter(writer);
		}

		public void print(Object... objects) {
			for (int i = 0; i < objects.length; i++) {
				if (i != 0)
					writer.print(' ');
				writer.print(objects[i]);
			}
		}

		public void println() {
			writer.print("\n");
		}

		public void printLine(Object... objects) {
			print(objects);
			writer.println();
		}

		public void close() {
			writer.close();
		}

		public void flush() {
			writer.flush();
		}

	}

	private static final FastReader fs = new FastReader();
	private static final OutputWriter out = new OutputWriter(System.out);
}