#include <stdio.h>

int sum(int a);

int main(){
	while(1){
		int a;
		scanf("%d",&a);
		if(a==0)
			break;
		int suma=sum(a);
		int b=11;
		while(suma!=sum(b*a)){
			++b;
		}
		printf("%d\n",b);
	}
	return 0;
}

int sum(int a){
	int suma=0;
	while(a>0){
		suma+=a%10;
		a/=10;	
	}
	return suma;
}