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#include <iostream> #include <cstdlib> #include <cstdio> #include <cstring> using namespace std; #define maxn 10000000 int n; long long q[maxn]; long long work() { int front = 0; int rear = 0; q[rear++] = 1; while (1) { long long temp = q[front++]; if ((temp * 10) % n == 0) return temp * 10; if ((temp * 10 + 1) % n == 0) return temp * 10 + 1; q[rear++] = temp * 10; q[rear++] = temp * 10 + 1; } return -1; } int main() { // for (n = 1; n <= 200; n++) // printf("%lld\n", work()); while (scanf("%d", &n), n) printf("%lld\n", work()); }