#include <bits/stdc++.h>

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int N;
    cin >> N;
    int day = 0;
    while (N > 0) {
        day++;
        N--;
        if (day % 7 == 0) {
            N += 6;
        }
    }
    cout << day << endl;
    return 0;
}