#include <stdio.h>

int main() {
	int a;
	while (scanf("%d", &a), a > 0) {
		int sum = 0, sum2;
		long long x, t;
		t = a;
		while (t > 0) {
			sum += t % 10;
			t /= 10;
		}
		x = 11;
		while (1) {
			sum2 = 0;
			t = x*a;
			while (t > 0) {
				sum2 += t % 10;
				t /= 10;
			}
			if (sum == sum2) {
				printf("%lld\n", x);
				break;
			}
			x++;
		}
	}
	return 0;
}