import java.util.*;

public class easy {
    static Scanner sc = new Scanner(System.in);

    public static void main(String[] args) {
        int vstup;
        while ((vstup = sc.nextInt()) != 0) {
            System.out.println(vypocti(vstup));
        }
    }
    
    static int s(int x){
    
        int y = 0;
        while (x> 0){
            y += x%10;
            x=x/10;
        }
        return y;
    }
    
    static int vypocti(int vstup) {
        int p = 11;
        while (s(vstup) != s(vstup*p)) {
            p++;
        }
        return p;
    }
}