#include <cstdio>

long long cs(long long x) {
  long long res = 0;
  while (x) {
    res += x%10;
    x /= 10;
  }
  return res;
}

int main() {
  long long n;
  scanf("%lld", &n);
  while (n) {
    long long target = cs(n);
    long long res = 11;
    while (cs(res*n) != target) ++res;
    printf("%lld\n", res);
    scanf("%lld", &n);
  }
  return 0;
}