#include <bits/stdc++.h>
using namespace std;
using namespace chrono;

vector<string> strings{
        "RGB",
        "GRB",
        "GBR",
        "BGR",
        "BRG",
        "RBG"
};

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int n; cin >> n;
    for (int i = 1; i <= 10; i++) if (n*i % 10 == 0) {
        cout << i;
        break;
    }
}