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.*;
import java.math.BigInteger;
import java.util.*;

/**
 * Created by alsergeev on 27.12.2016.
 */

public class EasyTask {
    public static void main(String args[]) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);

        TaskA solver = new TaskA();
        solver.solve(1, in, out);

        out.close();
    }
}

class TaskA {
    public int min(int a, int b) { return a < b ? a : b; }
    public int max(int a, int b) { return a < b ? b : a; }

    public int gcd(int a, int b) {
        return b == 0 ? a : gcd(b, a%b);
    }

    public void solve(int testNumber, InputReader in, PrintWriter out) {
        int n = in.nextInt();
        String s = in.nextLine().toLowerCase();

        int a[] = new int[26];
        int count = 0;

        for (int i = 0; i < n; ++i) {
            a[s.charAt(i)-97] = 1;
        }

        for (int i = 0; i < 26; ++i) {
            count += a[i];
        }

        if (count == 26) out.println("YES");
        else out.println("NO");
    }
}

class InputReader {
    BufferedReader in;
    StringTokenizer st;

    public InputReader(InputStream stream) {
        in = new BufferedReader(new InputStreamReader(stream));
        eat("");
    }

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

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

    public String next() {
        while (!st.hasMoreTokens())
            eat(nextLine());
        return st.nextToken();
    }

    public String nextLine() {
        try {
            return in.readLine();
        } catch (IOException e) {
            throw new InputMismatchException();
        }
    }

    public void eat(String str) {
        if (str == null) throw new InputMismatchException();
        st = new StringTokenizer(str);
    }
}