

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.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.InputMismatchException;
import java.util.List;

public class Main {

	public Main() throws FileNotFoundException {

//		File file = Paths.get("input.txt").toFile();
//		if (file.exists()) {
//			System.setIn(new FileInputStream(file));
//		}
		// long t = System.currentTimeMillis();

		InputReader reader = new InputReader();

		String str=reader.nextLine();
		
		if(str.length()<=2) {
			System.out.println("YES");
		}else {
			int i1=str.charAt(0)-'A';
			int i2=str.charAt(1)-'A';
			boolean ok=true;
			for(int i=2;i<str.length();i++) {
				int i3=str.charAt(i)-'A';
				if((i1+i2)%26==i3) {
					i1=i2;
					i2=i3;
				}else {
					ok=false;
					break;
				}
			}
			if(ok) {
				System.out.println("YES");
			}else {
				System.out.println("NO");
			}
		}
		

		
//		int val=reader.nextInt();
//		System.out.println((int)Math.sqrt(val));
	}
	
	

	static class InputReader {
		private byte[] buf = new byte[16384];
		private int curChar;
		private int numChars;

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

		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 String nextString() {
			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 long nextLong() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			long res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}

		public int nextInt() {
			int c = read();
			while (isSpaceChar(c))
				c = read();
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = read();
			}
			int res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = read();
			} while (!isSpaceChar(c));
			return res * sgn;
		}

		public int[] nextIntArray(int n) {
			int[] arr = new int[n];
			for (int i = 0; i < n; i++) {
				arr[i] = nextInt();
			}
			return arr;
		}

		public long[] nextLongArray(int n) {
			long[] arr = new long[n];
			for (int i = 0; i < n; i++) {
				arr[i] = nextLong();
			}
			return arr;
		}

		private 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;
		}

	}

	public static void main(String[] args) throws FileNotFoundException {
		new Main();
	}

}
