#include <iostream>
#include <vector>

using namespace std;

bool isLeap(long long year) {
	if (year % 400 == 0) {
		return true;
	} else if (year % 100 == 0) {
		return false;
	} else if (year % 4 == 0) {
		return true;
	}
	return false;
}

int main() {
	long long n;
	cin >> n;
	vector<int> days;
	int sameDayCount = 0;
	int day = isLeap(2015) ? 2 : 1;
	days.push_back(day);
	for (int i = 1; ; ++i) {
		day = (day + (isLeap(2015 + i) ? 2 : 1)) % 7;
		if (i >= 400 && days[i - 400] == day) {
			break;
		}
		if (day == 0) {
			++sameDayCount;
		}
		days.push_back(day);
	}
	long long remaining = n - 2015;
	long long repeatTimes = remaining / days.size();
	long long result = repeatTimes * sameDayCount;
	remaining %= days.size();
	day = (isLeap(2015 + days.size() * repeatTimes) ? 2 : 1);
	for (long long i = 2015 + days.size() * repeatTimes + 1; i <= n; ++i) {
		day = (day + (isLeap(i) ? 2 : 1)) % 7;
		if (day == 0) {
			++result;
		}
	}
	cout << result << endl;
	return 0;
}