#include <bits/stdc++.h> using namespace std; #define For(i, a, b) for(int i = (a); i < (b); i++) #define rep(i, n) For(i, 0, n) #define rFor(i, a, b) for(int i = (a); i >= (b); i--) #define ALL(v) (v).begin(), (v).end() #define rALL(v) (v).rbegin(), (v).rend() using lint = long long; using ld = long double; int INF = 2000000000; lint LINF = 1000000000000000000; struct SetupIo { SetupIo() { ios::sync_with_stdio(false); cin.tie(nullptr); cout << fixed << setprecision(15); } } setupio; int main() { lint n; cin >> n; lint cur = 0; For(i, 1, n + 1) { cur = cur * 10 + 9; cur %= n; if (cur == 0) { cout << i << "\n"; return 0; } } }