7.2.2

import java.util.Scanner;
public class Main {


    static boolean IsDigit(char c)
    {

        int a=(int) c;
        if (a>=48 && a<=57) return true;
        else return false;
    }

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String a=in.nextLine();
        char b=a.charAt(0);
        if (IsDigit(b)) System.out.println("YES");
            else System.out.println("NO");
    }
}