#include <iostream>

using namespace std;
using LL = long long;

int main() {
    int N;
    cin >> N;

    int mod = 0;
    for (int i = 1; i <= N; i++) {
        mod = (mod * 10 + 9) % N;
        if (mod == 0) {
            cout << i << endl;
            break;
        }
    }
}