#include <bits/stdc++.h> using namespace std; using ll = long long; const int INF = 1e9 + 10; const ll INFL = 4e18; int main() { ll N; cin >> N; ll tmp = 9 % N, ans = 1; while (true) { if (tmp == 0) { cout << ans << endl; return 0; } ((tmp *= 10) += 9) %= N; ans++; } }