#include <stdio.h>

int suc;
int k;
int c[8];
int i;
/*
int cifry(int index, int zvysok)
{
	int pom = 0;
	if (c[index] != 0) pom = zvysok + k*c[index];
	else pom = zvysok;
	if(pom == 0) return 0;
	return pom % 10 + cifry(index++, pom/10);
}*/

int f(int n)
{
	if (n < 10) return n;
	else return n%10 + f(n/10);
}

int main() {
	int n;
	
	while (1) {	
		scanf("%d",&n);
		if (n==0) return 0;
		for(i = 0; i < 8; i++) c[i] = 0;		
		suc = 0;
		i = 0;
		int cislo = n;
		while (n != 0) {
			/*printf("%d\n",n);*/
			suc += n%10;
			c[i] = n%10;
			n /= 10;
			i++;
		}
		k = 11;		
		while (1) {
			/*printf("k = %d\n", k);*/
			if(f(cislo*k) == suc) break;
			k++;
		}
		printf("%d\n", k);
	}
	return 0;
}