One day Alex was creating a contest about his friends, but accidentally deleted it. Fortunately, all the problems were saved, but now he needs to find them among other problems.

But there are too many problems, to do it manually. Alex asks you to write a program, which will determine if a problem is from this contest by its name.

It is known, that problem is from this contest if and only if its name contains one of Alex's friends' name exactly once. His friends' names are "Danil", "Olya", "Slava", "Ann" and "Nikita".

Names are case sensitive.

Input

The only line contains string from lowercase and uppercase letters and "_" symbols of length, not more than 100 — the name of the problem.

Output

Print "YES", if problem is from this contest, and "NO" otherwise.

Examples

Input

Alex_and_broken_contest


Output

NO

Input

NikitaAndString


Output

YES

Input

Danil_and_Olya


Output

NO
import java.util.*;

import javax.swing.plaf.synth.SynthSpinnerUI;

import java.io.*;
import java.lang.*;
public class Main {
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		//DisjointSet set = new DisjointSet(26);
		
		InputReader sc1 = new InputReader(System.in);
		PrintWriter sc2 = new PrintWriter(System.out);
		String s = sc1.readString();
		String ss[] = new String[5];
		ss[0] = "Danil";
		ss[1] = "Olya";
		ss[2] = "Slava";
		ss[3] = "Ann";
		ss[4] = "Nikita";
		int count = 0;
		for(int i=0;i<s.length();i++) {
			if((i+ss[0].length() < s.length()+1 && s.substring(i, i+ss[0].length()).equals(ss[0]))) {
				count++;
			}
			if((i+ss[1].length() < s.length()+1 && s.substring(i, i+ss[1].length()).equals(ss[1]))) {
				count++;
			}
			if((i+ss[2].length() < s.length()+1 && s.substring(i, i+ss[2].length()).equals(ss[2]))) {
				count++;
			}
			if((i+ss[3].length() < s.length()+1&& s.substring(i, i+ss[3].length()).equals(ss[3]))) {
				count++;
			}
			if((i+ss[4].length() < s.length()+1 && s.substring(i, i+ss[4].length()).equals(ss[4]))) {
				count++;
			}
		}
		if(count==1) {
			System.out.println("YES");
		}
		else {
			System.out.println("NO");
		}
		sc2.close();
	}
//101001000
//012345678
	/*
	 * 	DIVISORS
	 * */
	public static void divsors(int n) {
		for(int i=1;i<=Math.sqrt(n)+1;i++) {
			if(n%i==0) {
				if(n/i==i) {
					System.out.print(i+" ");
				}
				else {
					System.out.print	(i+" "+n/i);
				}
			}
		}
	}
	
	/*
	 * 	GCD 
	 * */
	
	public static int GCD(int x, int y) {
		if(x==0) {
			return y;
		}
		return GCD(y%x, x);
	}
	
	/*
	 * 	GCD EXTENDED
	 * */
	
	public static int gcdExtended(int a, int b, int x, int y) {
		if(a==0) {
			x = 0;
			y = 1;
			return b;
		}
		
		int x1 = 1, y1 = 1;
		int gcd = gcdExtended(b%a, a, x1, y1);
		x = y1 - (b/a)*x1;
		y = x1;
		
		return gcd;
	}
	
	
	static class DisjointSet{
		static StringBuilder str = new StringBuilder();
		static int count = 0;
		int rank[];
		int parent[];
		int n;
		DisjointSet(int n){
			this.n = n;
			rank = new int[n];
			Arrays.fill(rank, 0);
			parent = new int[n];
			makeSet();
			
		}
		void makeSet() {
			for(int i=0;i<n;i++) {
				parent[i] = i;
			}
		}
		
		int find(int x) {
			if(parent[x]!=x) {
				parent[x] = find(parent[x]);
			}
			return parent[x];
		}
		
		void union(int x, int y) {
			int xRoot = find(x);
			int yRoot = find(y);
			
			if(xRoot==yRoot) {
				return;
			}
			
			if(rank[xRoot]>rank[yRoot]) {
				parent[yRoot] = xRoot;
				Append(x,y);
				count++;
			}
			else if(rank[xRoot]<rank[yRoot]) {
				parent[xRoot] = yRoot;
				Append(x,y);
				count++;
			}
			else {
				parent[yRoot] = xRoot;
				rank[xRoot] = rank[xRoot] + 1;
				count++;
				Append(x,y);
			}
		}
		
		void Append(int x, int y) {
			str.append((char)(x+97)+" "+(char)(y+97)+"\n");
		}
	}
	static class InputReader {
		 
		private final InputStream stream;
		private final byte[] buf = new byte[8192];
		private int curChar, snumChars;
		private SpaceCharFilter filter;
 
		public InputReader(InputStream stream) {
			this.stream = stream;
		}
 
		public int snext() {
			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 = snext();
			while (isSpaceChar(c))
				c = snext();
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = snext();
			}
			int res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = snext();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public long nextLong() {
			int c = snext();
			while (isSpaceChar(c))
				c = snext();
			int sgn = 1;
			if (c == '-') {
				sgn = -1;
				c = snext();
			}
			long res = 0;
			do {
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				res *= 10;
				res += c - '0';
				c = snext();
			} while (!isSpaceChar(c));
			return res * sgn;
		}
 
		public int[] nextIntArray(int n) {
			int a[] = new int[n];
			for (int i = 0; i < n; i++)
				a[i] = nextInt();
			return a;
		}
 
		public String readString() {
			int c = snext();
			while (isSpaceChar(c))
				c = snext();
			StringBuilder res = new StringBuilder();
			do {
				res.appendCodePoint(c);
				c = snext();
			} while (!isSpaceChar(c));
			return res.toString();
		}
 
		public boolean isSpaceChar(int c) {
			if (filter != null)
				return filter.isSpaceChar(c);
			return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
		}
 
		public interface SpaceCharFilter {
			public boolean isSpaceChar(int ch);
		}
	}	
}

