#include<algorithm>
#include<complex>
#include<cstdio>
#include<iostream>
#include<queue>

using namespace std;

bool is_uruu(long long n){
	if(n%4==0 && n%100!=0 && n%400!=0)
		return true;
	return false;
}

int amari(int b){
	if(b<6)return 0;
	else if(b<11)return 1;
	else if(b<17)return 2;
	else if(b<28)return 3;
	return 3;
}

int main(void){
	long long n;
	cin >> n;
	// 2014/7/23/wed
	long long k = 2041;
	long long uruu = (n/4 - n/100 + n/400) - (k/4 - k/100 + k/400);
	
	if(n < 2019)cout << 0 << endl;
	else if(n < 2024)cout << 1 << endl;
	else if(n < 2030)cout << 2 << endl;
	else if(n < 2041)cout << 3 << endl;
	else if(n == 2041)cout << 4 << endl;

	else cout << ((n-k)/28)*4 + amari((n-k)%28) + 4<< endl;

	return 0;
}