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

typedef long long ll;
typedef pair<int,int>pint;
typedef vector<int>vint;
typedef vector<pint>vpint;
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define all(v) (v).begin(),(v).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define reps(i,f,n) for(int i=(f);i<(n);i++)
#define each(it,v) for(__typeof((v).begin()) it=(v).begin();it!=(v).end();it++)
template<class T,class U>void chmin(T &t,U f){if(t>f)t=f;}
template<class T,class U>void chmax(T &t,U f){if(t<f)t=f;}

int m[]={31,28,31,30,31,30,31,31,30,31,30,31};
bool is_uruu(int y){return y%400==0||(y%4==0&&y%100!=0);}

int lis[101010];

signed main(){
    lis[2014]=3;
    for(int i=2015;i<101010;i++){
        lis[i]=(lis[i-1]+365+is_uruu(i))%7;
    }

    int N;cin>>N;
    if(N<4000){
        int tmp=0;
        for(int i=2015;i<=N;i++)tmp+=lis[i]==3;
        cout<<tmp<<endl;
        return 0;
    }

    int tmp=0;
    for(int i=2015;i<4000;i++)tmp+=lis[i]==3;
    int x=0;
    for(int i=4000;i<4000+2800;i++)x+=lis[i]==3;
    tmp+=(N-4000)/2800*x;
    N=4000+(N-4000)%2800;
    for(int i=4000;i<=N;i++)tmp+=lis[i]==3;
    cout<<tmp<<endl;
    return 0;
}