

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

//package com.live.april_2021.april_fool_day;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;
import java.util.LinkedList;

public class Problem3 {
	String INPUT = "";

	public static void main(String[] args) throws Exception {
		new Problem3().run();
	}

	public static long gcd(long a, long b) {
		if (a == 0)
			return b;

		return gcd(b % a, a);
	}

	private void solve() throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String str = br.readLine();
		if (str.length() <= 2) {
			System.out.println("YES");
		} else {
			boolean result = true;
			for (int i = 2; i < str.length(); i++) {
				int sum = str.charAt(i - 1) + str.charAt(i - 2) - 'A' - 'A' + 1;
				sum = sum % 26;

				if (str.charAt(i) - 'A' + 1 == sum) {

				} else {
					result = false;
				}
			}
			if (result) {
				System.out.println("YES");
			} else {
				System.out.println("NO");
			}
		}
	}

	InputStream is;
	PrintWriter out;

	void run() throws Exception {
		is = oj ? System.in : new ByteArrayInputStream(INPUT.getBytes());
		out = new PrintWriter(System.out);

		long s = System.currentTimeMillis();
		solve();
		out.flush();
		tr(System.currentTimeMillis() - s + "ms");
	}

	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 nextDouble() {
		return Double.parseDouble(nextString());
	}

	private char nextCharactor() {
		return (char) skip();
	}

	private String nextString() {
		int b = skip();
		StringBuilder sb = new StringBuilder();
		while (!(isSpaceChar(b))) { // when nextLine, (isSpaceChar(b) && b !=
									// ' ')
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}

	private char[] nextString(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 char[][] nextMap(int n, int m) {
		char[][] map = new char[n][];
		for (int i = 0; i < n; i++)
			map[i] = nextString(m);
		return map;
	}

	private int[] nextIntArr(int n) {
		int[] a = new int[n];
		for (int i = 0; i < n; i++)
			a[i] = nextInt();
		return a;
	}

	private int nextInt() {
		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 nextLong() {
		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 = true;// System.getProperty("ONLINE_JUDGE") != null;

	private void tr(Object... o) {
		if (!oj)
			System.out.println(Arrays.deepToString(o));
	}
}
