

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.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.InputMismatchException;

public class C {
	// author: Nagabhushan S Baddi

	// PRIMARY VARIABLES
	private static int n, m;
	private static int[] a, b;
	private static long ans;
	private static int[][] id, dp;
	private static int idf;
	private static String s, t;
	private static HashMap<Integer, ArrayList<Integer>> g;

	// CONSTANTS
	private static final int MOD = (int) 1e9 + 7;

	public static void main(String[] args) {
		s = ins();
		boolean good = true;
		for(int i=2; i<s.length(); i++) {
			if ((s.charAt(i-1)+s.charAt(i-2)-'A'-'A')%26 == s.charAt(i)-'A') {
//				System.out.println((char)(s.charAt(i-1)+s.charAt(i-2)-1-'A'-'A'+'A'));
			} else {
				good = false;
				break;
			}
		}

		println(good?"YES":"NO");
		
		out.flush();
		out.close();

	}

	// INIT
	private static void initCase(int z) {
		idf = z;
		ans = 0;
	}

	// PRINT ANSWER
	private static void printAns(Object o) {
		out.println(o);
	}

	private static void printAns(Object o, int testCaseNo) {
		out.println("Case #" + testCaseNo + ": " + o);
	}

	private static void printArray(Object[] a) {
		for (int i = 0; i < a.length; i++) {
			out.print(a[i] + " ");
		}
		out.println();
	}

	// SORT SHORTCUTS - QUICK SORT TO MERGE SORT
	private static void sort(int[] a) {
		int n = a.length;
		Integer[] b = new Integer[n];
		for (int i = 0; i < n; i++) {
			b[i] = a[i];
		}

		Arrays.sort(b);

		for (int i = 0; i < n; i++) {
			a[i] = b[i];
		}
	}

	private static void sort(long[] a) {
		int n = a.length;
		Long[] b = new Long[n];
		for (int i = 0; i < n; i++) {
			b[i] = a[i];
		}

		Arrays.sort(b);

		for (int i = 0; i < n; i++) {
			a[i] = b[i];
		}
	}

	// INPUT SHORTCUTS

	private static int[] ina(int n) {
		int[] temp = new int[n];
		for (int i = 0; i < n; i++) {
			temp[i] = in.nextInt();
		}
		return temp;
	}

	private static int[][] ina2d(int n, int m) {
		int[][] temp = new int[n][m];
		for (int i = 0; i < n; i++) {
			temp[i] = ina(m);
		}
		return temp;
	}

	private static int ini() {
		return in.nextInt();
	}

	private static long inl() {
		return in.nextLong();
	}

	private static double ind() {
		return Double.parseDouble(ins());
	}

	private static String ins() {
		return in.readString();
	}

	// PRINT SHORTCUTS
	private static void println(Object... o) {
		for (Object x : o) {
			out.write(x + "");
		}
		out.write("\n");
	}

	private static void pd(Object... o) {
		for (Object x : o) {
			out.write(x + "");
		}
		out.flush();
		out.write("\n");
	}

	private static void print(Object... o) {
		for (Object x : o) {
			out.write(x + "");
		}
	}

	// GRAPH SHORTCUTS
	private static HashMap<Integer, ArrayList<Integer>> intree(int n) {

		HashMap<Integer, ArrayList<Integer>> g = new HashMap<>();
		for (int i = 0; i < n; i++) {
			g.put(i, new ArrayList<>());
		}

		for (int i = 0; i < n - 1; i++) {
			int u = ini() - 1;
			int v = ini() - 1;
			g.get(u).add(v);
			g.get(v).add(u);
		}

		return g;
	}

	private static HashMap<Integer, ArrayList<Integer>> ingraph(int n, int m) {
		HashMap<Integer, ArrayList<Integer>> g = new HashMap<>();

		for (int i = 0; i < n; i++) {
			g.put(i, new ArrayList<>());
		}

		for (int i = 0; i < m; i++) {
			int u = ini() - 1;
			int v = ini() - 1;
			g.get(u).add(v);
			g.get(v).add(u);
		}

		return g;

	}

	private static HashMap<Integer, ArrayList<Integer>> indirectedgraph(int n, int m) {
		HashMap<Integer, ArrayList<Integer>> g = new HashMap<>();

		for (int i = 0; i < n; i++) {
			g.put(i, new ArrayList<>());
		}

		for (int i = 0; i < m; i++) {
			int u = ini() - 1;
			int v = ini() - 1;
			g.get(u).add(v);
		}

		return g;

	}

	private static HashMap<Integer, ArrayList<Edge>> inweightedgraph(int n, int m) {
		HashMap<Integer, ArrayList<Edge>> g = new HashMap<>();

		for (int i = 0; i < n; i++) {
			g.put(i, new ArrayList<>());
		}

		for (int i = 0; i < m; i++) {
			int u = ini() - 1;
			int v = ini() - 1;
			int w = ini();
			Edge edge = new Edge(u, v, w);
			g.get(u).add(edge);
			g.get(v).add(edge);
		}

		return g;

	}

	private static class Edge implements Comparable<Edge> {
		private int u, v;
		private long w;

		public Edge(int a, int b, long c) {
			u = a;
			v = b;
			w = c;
		}

		public int other(int x) {
			return (x == u ? v : u);
		}

		public int compareTo(Edge edge) {
			return Long.compare(w, edge.w);
		}
	}

	private static class Pair {
		private int u, v;

		public Pair(int a, int b) {
			u = a;
			v = b;
		}

		public int hashCode() {
			return u + v + u * v;
		}

		public boolean equals(Object object) {
			Pair pair = (Pair) object;
			return u == pair.u && v == pair.v;
		}
	}

	private static class Node implements Comparable<Node> {
		private int u;
		private long dist;

		public Node(int a, long b) {
			u = a;
			dist = b;
		}

		public int compareTo(Node node) {
			return Long.compare(dist, node.dist);
		}
	}

	// MATHS AND NUMBER THEORY SHORTCUTS
	private static int gcd(int a, int b) {
		// O(log(min(a,b)))
		if (b == 0)
			return a;

		return gcd(b, a % b);
	}

	private static long modExp(long a, long b) {
		if (b == 0)
			return 1;

		a %= MOD;

		long exp = modExp(a, b / 2);

		if (b % 2 == 0) {
			return (exp * exp) % MOD;
		} else {
			return (a * ((exp * exp) % MOD)) % MOD;
		}
	}

	private long mul(int a, int b) {
		return a * 1L * b;
	}

	// Segment Tree
	private static class SegmentTree<T extends Comparable<T>> {
		private int n, m;
		private T[] a;
		private T[] seg;
		private T NULLVALUE;

		public SegmentTree(int n, T NULLVALUE) {
			this.NULLVALUE = NULLVALUE;
			this.n = n;
			m = 4 * n;
			seg = (T[]) new Object[m];

		}

		public SegmentTree(T[] a, int n, T NULLVALUE) {
			this.NULLVALUE = NULLVALUE;
			this.a = a;
			this.n = n;
			m = 4 * n;
			seg = (T[]) new Object[m];
			construct(0, n - 1, 0);
		}

		private void update(int pos) {
			// Range Sum
			// seg[pos] = seg[2*pos+1]+seg[2*pos+2];

			// Range Min
			if (seg[2 * pos + 1].compareTo(seg[2 * pos + 2]) <= 0) {
				seg[pos] = seg[2 * pos + 1];
			} else {
				seg[pos] = seg[2 * pos + 2];
			}
		}

		private T optimum(T leftValue, T rightValue) {
			// Range Sum
			// return leftValue+rightValue;

			// Range Min
			if (leftValue.compareTo(rightValue) <= 0) {
				return leftValue;
			} else {
				return rightValue;
			}
		}

		public void construct(int low, int high, int pos) {
			if (low == high) {
				seg[pos] = a[low];
				return;
			}

			int mid = (low + high) / 2;

			construct(low, mid, 2 * pos + 1);
			construct(mid + 1, high, 2 * pos + 2);
			update(pos);
		}

		public void add(int index, T value) {
			add(index, value, 0, n - 1, 0);
		}

		private void add(int index, T value, int low, int high, int pos) {
			if (low == high) {
				seg[pos] = value;
				return;
			}

			int mid = (low + high) / 2;

			if (index <= mid) {
				add(index, value, low, mid, 2 * pos + 1);
			} else {
				add(index, value, mid + 1, high, 2 * pos + 2);
			}
			update(pos);
		}

		public T get(int qlow, int qhigh) {
			return get(qlow, qhigh, 0, n - 1, 0);
		}

		public T get(int qlow, int qhigh, int low, int high, int pos) {
			if (qlow > low || low > qhigh) {
				return NULLVALUE;
			} else if (qlow <= low || qhigh >= high) {
				return seg[pos];
			} else {
				int mid = (low + high) / 2;
				T leftValue = get(qlow, qhigh, low, mid, 2 * pos + 1);
				T rightValue = get(qlow, qhigh, mid + 1, high, 2 * pos + 2);

				return optimum(leftValue, rightValue);
			}
		}
	}

	// DSU
	private static class DSU {
		private int[] id;
		private int[] size;
		private int n;

		public DSU(int n) {
			this.n = n;

			id = new int[n];
			for (int i = 0; i < n; i++) {
				id[i] = i;
			}

			size = new int[n];
			Arrays.fill(size, 1);
		}

		private int root(int u) {
			while (u != id[u]) {
				id[u] = id[id[u]];
				u = id[u];
			}
			return u;
		}

		public boolean connected(int u, int v) {
			return root(u) == root(v);
		}

		public void union(int u, int v) {
			int p = root(u);
			int q = root(v);

			if (size[p] >= size[q]) {
				id[q] = p;
				size[p] += size[q];
			} else {
				id[p] = q;
				size[q] += size[p];
			}
		}
	}

	// FAST INPUT OUTPUT LIBRARY
	private static InputReader in = new InputReader(System.in);
	private static PrintWriter out = new PrintWriter(System.out);

	private static class InputReader {

		private final InputStream stream;
		private final byte[] buf = new byte[8192];
		private int curChar, snumChars;

		public InputReader(InputStream st) {
			this.stream = st;
		}

		public int read() {
			if (snumChars == -1)
				throw new InputMismatchException();
			if (curChar >= snumChars) {
				curChar = 0;
				try {
					snumChars = stream.read(buf);
				} catch (IOException e) {
					throw new InputMismatchException();
				}
				if (snumChars <= 0)
					return -1;
			}
			return buf[curChar++];
		}

		public int nextInt() {
			int c = read();
			while (isSpaceChar(c)) {
				c = read();
			}
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			int res = 0;
			do {
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}

		public long nextLong() {
			int c = read();
			while (isSpaceChar(c)) {
				c = read();
			}
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			long res = 0;
			do {
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}

		public String readString() {
			int c = read();
			while (isSpaceChar(c)) {
				c = read();
			}
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isSpaceChar(c));
			return res.toString();
		}

		public String nextLine() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = read();
			} while (!isEndOfLine(c));
			return res.toString();
		}

		public boolean isSpaceChar(int c) {
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}

		private boolean isEndOfLine(int c) {
			return c == '\n' || c == '\r' || c == -1;
		}

	}
}


