#include "bits/stdc++.h"
using namespace std;



int main(){
	long long N;
	cin >> N;
	//N = 2014 + 2800;
	long long day = 0;
	long long nokori = N - 2014;
	long long ans = 0;

	long long mul = nokori / 2800;
	ans += mul * 399;
	nokori %= 2800;
	for (int i = 0; i < nokori; i++)
	{
		int y = 2015 + i;
		if (y % 400 == 0) day += 366;
		else if (y % 100 == 0) day += 365;
		else if (y % 4 == 0) day += 366;
		else day += 365;
		if (day % 7 == 0) ans ++;
	}
	cout << ans << endl;
}