Problem: A word or a sentence in some language is called a pangram if all the characters of the alphabet of this language appear in it at least once. Pangrams are often used to demonstrate fonts in printing or test the output devices.

You are given a string consisting of lowercase and uppercase Latin letters. Check whether this string is a pangram. We say that the string contains a letter of the Latin alphabet if this letter occurs in the string in uppercase or lowercase.

Input

The first line contains a single integer n (1 ≤ n ≤ 100) — the number of characters in the string.

The second line contains the string. The string consists only of uppercase and lowercase Latin letters.

Output

Output "YES", if the string is a pangram and "NO" otherwise.

Examples

Input

12
toosmallword


Output

NO


Input

35
TheQuickBrownFoxJumpsOverTheLazyDog


Output

YES

Solution (in JAVA):

Solution:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Set;
import java.util.Stack;
import java.util.StringTokenizer;
import java.util.TreeMap;
import java.util.TreeSet;

public class Main {
    static Main.MyScanner sc = new Main.MyScanner();
    // static Main.Parser sc = new Parser(System.in);
    static PrintWriter out = new PrintWriter(System.out, true);

    public static void main(String[] args) throws Exception {
    	int n = sc.nextInt();
    	String s = sc.next();
    	boolean dp[] = new boolean[26];
    	int count = 26;
    	for(int i = 0 ; i < n ; i++){
    		char temp = s.charAt(i);
    		if(temp > 90)
    			temp -= 32;
    		if(!dp[temp-65]){
    			dp[temp-65] = true;
    			count --;
    		}
    	}
    	if(count == 0)
    		out.println("YES");
    	else
    		out.print("NO");
    	
        out.close();
    }

	static private class MyScanner {
        BufferedReader br;
        StringTokenizer st;

        public MyScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        public int mod(long x) {
            return (int) x % 1000000007;
        }

        public int mod(int x) {
            return x % 1000000007;
        }

        boolean hasNext() {
            if (st.hasMoreElements())
                return true;
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                e.printStackTrace();
            }
            return st.hasMoreTokens();
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }

        public long nextLong() {
            return Long.parseLong(next());
        }
    }

    static class Parser {
        final private int BUFFER_SIZE = 65536; // 2^16, a good compromise for
                                                // some problems
        private InputStream din; // Underlying input stream
        private byte[] buffer; // Self-maintained buffer
        private int bufferPointer; // Current read position in the buffer
        private int bytesRead; // Effective bytes in the buffer read from the
                                // input stream

        public Parser(InputStream in) {
            din = in;
            buffer = new byte[BUFFER_SIZE];
            bufferPointer = bytesRead = 0;
        }

        /**
         * Read the next integer from the input stream.
         * 
         * @return The next integer.
         * @throws IOException
         */
        public int nextInt() throws IOException {
            int result = 0;
            byte c = read();
            while (c <= ' ')
                c = read();
            boolean neg = (c == '-');
            if (neg)
                c = read();
            while (c >= '0' && c <= '9') {
                result = result * 10 + c - '0';
                c = read();
            }
            if (neg)
                return -result;
            return result;
        }

        /**
         * Read the next byte of data from the input stream.
         * 
         * @return the next byte of data, or -1 if the end of the stream is
         *         reached.
         * @throws IOException
         *             if an I/O error occurs.
         */
        public byte read() throws IOException {
            if (bufferPointer == bytesRead)
                fillBuffer();
            return buffer[bufferPointer++];
        }

        /**
         * Read data from the input stream into the buffer
         * 
         * @throws IOException
         *             if an I/O error occurs.
         */
        private void fillBuffer() throws IOException {
            bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
            if (bytesRead == -1)
                buffer[0] = -1;
        }
    }
}