// {{{ Templates
#include <bits/stdc++.h>

#define show(x) cerr << #x << " = " << x << endl

using namespace std;
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;

template <typename T>
ostream& operator<<(ostream& os, const vector<T>& v)
{
    os << "sz:" << v.size() << "\n[";
    for (const auto& p : v) {
        os << p << ",";
    }
    os << "]\n";
    return os;
}

template <typename S, typename T>
ostream& operator<<(ostream& os, const pair<S, T>& p)
{
    os << "(" << p.first << "," << p.second
       << ")";
    return os;
}


constexpr ll MOD = (ll)1e9 + 7LL;

template <typename T>
constexpr T INF = numeric_limits<T>::max() / 100;

// }}}

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    ll N;
    cin >> N;
    constexpr ll START = 2015;
    const ll years = N - START + 1;
    constexpr ll LOOP = 400;
    ll loop = 0;
    ll plus = 0;
    for (ll i = 0; i < LOOP; i++) {
        const ll y = START + i;
        if (y % 400 == 0) {
            plus += 2;
        } else if (y % 100 == 0) {
            plus++;
        } else if (y % 4 == 0) {
            plus += 2;
        } else {
            plus++;
        }
        if (plus % 7 == 0) {
            loop++;
        }
    }
    const ll loops = years / LOOP;
    ll cnt = loops * loop;
    plus = 0;
    const ll start = START + LOOP * loops;
    for (ll y = start; y <= N; y++) {
        if (y % 400 == 0) {
            plus += 2;
        } else if (y % 100 == 0) {
            plus++;
        } else if (y % 4 == 0) {
            plus += 2;
        } else {
            plus++;
        }
        if (plus % 7 == 0) {
            cnt++;
        }
    }
    cout << cnt << endl;


    return 0;
}