import java.util.Scanner;

public class MaxDigits {

   public static void main(String[] args) {
      Scanner input=new Scanner(System.in);
      long n;
      long max=0;
      System.out.println("plz eter a enteger number: ");
      n = input.nextLong();
      while(n!=0){
         if(n%10>max){
            max=n%10;
            n/=10;
         }
      }
      System.out.println("max = " + max);

   }
}