#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint1000000007;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf 100000000000000000


int main(){
	
	long long N;
	cin>>N;
	
	vector<int> start(7,0);
	int sum = 0;
	rep(i,7){
		int cur = i;
		rep(j,400){
			cur++;
			if(j%400==0)cur++;
			else if(j%100!=0&&j%4==0)cur++;
			cur %= 7;
			if(cur==0)start[i] ++;
		}
		if(i==0)sum = cur;
	}
	
	long long ans = 0LL;
	int cur = 0;
	for(long long i=2015;i<=N;i++){
		if(i%400==0 && i+399<=N){
			ans += start[cur];
			cur += sum;
			cur %= 7;
			i+=399;
		}
		else{
			cur ++;
			if(i%400==0)cur++;
			else if(i%100!=0&&i%4==0)cur++;
			cur%=7;
			if(cur==0)ans++;
		}
	}
	cout<<ans<<endl;
	return 0;
}