Problem: 

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

Solution (in JAVA):

Solution:
import java.io.*;
import java.math.*;
import java.util.*;

public class F_elementary {
	public static int works(String[] arr, String str, int count) {
		if (str.length() == 0) {
			count++;
		}
		
		else {
			boolean x = false;
			for (int i = 0; i < arr.length; i++) {
				if (str.length() >= 2 && str.substring(0,1).equals(arr[i]) && str.substring(0,2).equals(arr[i])) {
					String temp = str;
					String temp2 = str;
					count += works(arr, str.substring(1), count);
					count += works(arr, str.substring(2), count);
					x = true;
				}
				else if (str.length() >= 1 && str.substring(0,1).equals(arr[i])) {
					count += works(arr, str.substring(1), count);
					x = true;
				}
				else if (str.length() >= 2 && str.substring(0,2).equals(arr[i])) {
					count += works(arr, str.substring(2), count);
					x = true;
				}
			}
			if (x == false) {
				return count;
			}
		}
		return count;
	}
    public static void main(String[] args) throws IOException {
        FastScanner sc = new FastScanner(System.in);
        PrintWriter pw = new PrintWriter(System.out);
        
        String str = sc.next();
        String[] arr = {"H", "HE", "LI", "BE", "B", "C", "N", "O", "F", "NE", "NA", "MG", "AL", "SI", "P", "S", "CL", "AR", "K", "CA", "SC", "TI", "V", "CR", "MN", "FE", "CO", "NI", "CU", "ZN", "GA", "GE", "AS", "SE", "BR", "KR", "RB", "SR", "Y", "ZR", "NB", "MO", "TC", "RU", "RH", "PD", "AG", "CD", "IN", "SN", "SB", "TE", "I", "XE", "CS", "BA", "LA", "CE", "PR", "ND", "PM", "SM", "EU", "GD", "TB", "DY", "HO", "ER", "TM", "YB", "LU", "HF", "TA", "W", "RE", "OS", "IR", "PT", "AU", "HG", "TL", "PB", "BI", "PO", "AT", "RN", "FR", "RA", "AC", "TH", "PA", "U", "NP", "PU", "AM", "CM", "BK", "CF", "ES", "FM", "MD", "NO", "LR", "RF", "DB", "SG", "BH", "HS", "MT", "DS", "RG", "CN", "NH", "FL", "MC", "LV", "TS", "OG"};
        if(works(arr, str, 0) >= 1) {
        	pw.println("YES");
        }
        else pw.println("NO");
        
        pw.close();
    }
    static class FastScanner {
    	private boolean finished = false;

        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private SpaceCharFilter filter;

        public FastScanner(InputStream stream) {
            this.stream = stream;
        }

        public int read() {
            if (numChars == -1) {
                throw   new InputMismatchException();
            }
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar++];
        }
        public int peek() {
            if (numChars == -1) {
                return -1;
            }
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    return -1;
                }
                if (numChars <= 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 {
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                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 {
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

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

        public boolean isSpaceChar(int c) {
            if (filter != null) {
                return filter.isSpaceChar(c);
            }
            return isWhitespace(c);
        }

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

        private String readLine0() {
            StringBuilder buf = new StringBuilder();
            int c = read();
            while (c != '\n' && c != -1) {
                if (c != '\r') {
                    buf.appendCodePoint(c);
                }
                c = read();
            }
            return buf.toString();
        }
        public String readLine() {
            String s = readLine0();
            while (s.trim().length() == 0) {
                s = readLine0();
            }
            return s;
        }
        public String readLine(boolean ignoreEmptyLines) {
            if (ignoreEmptyLines) {
                return readLine();
            } else {
                return readLine0();
            }
        }

        public BigInteger readBigInteger() {
            try {
                return new BigInteger(nextString());
            } catch (NumberFormatException e) {
                throw new InputMismatchException();
            }
        }

        public char nextCharacter() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            return (char) c;
        }

        public double nextDouble() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            double res = 0;
            while (!isSpaceChar(c) && c != '.') {
                if (c == 'e' || c == 'E') {
                    return res * Math.pow(10, nextInt());
                }
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            }
            if (c == '.') {
                c = read();
                double m = 1;
                while (!isSpaceChar(c)) {
                    if (c == 'e' || c == 'E') {
                        return res * Math.pow(10, nextInt());
                    }
                    if (c < '0' || c > '9') {
                        throw new InputMismatchException();
                    }
                    m /= 10;
                    res += (c - '0') * m;
                    c = read();
                }
            }
            return res * sgn;
        }

        public boolean isExhausted() {
            int value;
            while (isSpaceChar(value = peek()) && value != -1) {
                read();
            }
            return value == -1;
        }
    public String next() {
            return nextString();
        }

        public SpaceCharFilter getFilter() {
            return filter;
        }

        public void setFilter(SpaceCharFilter filter) {
            this.filter = filter;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);
        }
        public int[] nextIntArray(int n){
            int[] array=new int[n];
            for(int i=0;i<n;++i)array[i]=nextInt();
            return array;
        }
        public int[] nextSortedIntArray(int n){
            int array[]=nextIntArray(n);
            PriorityQueue<Integer> pq = new PriorityQueue<Integer>();
            for(int i = 0; i < n; i++){
                pq.add(array[i]);
            }
            int[] out = new int[n];
            for(int i = 0; i < n; i++){
                out[i] = pq.poll();
            }
            return out;
        }
        public int[] nextSumIntArray(int n){
            int[] array=new int[n];
            array[0]=nextInt();
            for(int i=1;i<n;++i)array[i]=array[i-1]+nextInt();
            return array;
        }
        public ArrayList<Integer>[] nextGraph(int n, int m){
            ArrayList<Integer>[] adj = new ArrayList[n];
            for(int i = 0; i < n; i++){
                adj[i] = new ArrayList<Integer>();
            }
            for(int i = 0; i < m; i++){
                int u = nextInt(); int v = nextInt();
                u--; v--;
                adj[u].add(v); adj[v].add(u);
            }
            return adj;
        }
        public ArrayList<Integer>[] nextTree(int n){
            return nextGraph(n, n-1);
        }

        public long[] nextLongArray(int n){
            long[] array=new long[n];
            for(int i=0;i<n;++i)array[i]=nextLong();
            return array;
        }
        public long[] nextSumLongArray(int n){
            long[] array=new long[n];
            array[0]=nextInt();
            for(int i=1;i<n;++i)array[i]=array[i-1]+nextInt();
            return array;
        }
        public long[] nextSortedLongArray(int n){
            long array[]=nextLongArray(n);
            Arrays.sort(array);
            return array;
        }
    }
	static void shuffle(int[] a) {
		Random get = new Random();
		for (int i = 0; i < a.length; i++) {
			int r = get.nextInt(a.length);
			int temp = a[i];
			a[i] = a[r];
			a[r] = temp;
		}
	}
	static void shuffle(long[] a) {
		Random get = new Random();
		for (int i = 0; i < a.length; i++) {
			int r = get.nextInt(a.length);
			long temp = a[i];
			a[i] = a[r];
			a[r] = temp;
		}
	}
}