#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int main() {
	ll N;
	cin >> N;
	ll K = 1;
	ll x = 10 % N;
	while (x != 1) {
		x = x * 10 % N;
		K++;
	}
	cout << K << endl;
	return 0;
}