#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for(int i=0; i<(int)(n); i++)
#define FOR(i,b,e) for (int i=(int)(b); i<(int)(e); i++)
#define ALL(x) (x).begin(), (x).end()

const double PI = acos(-1);

int zeller(long long y, int m, int d) {
  if (m == 1 || m == 2) {
    m += 12;
    --y;
  }
  int h = (d + (13 * (m + 1)) / 5 + y + y / 4 - y / 100 + y / 400) % 7;
  return h;
}

long long dp[400][7];
long long sum[400][7];

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  
  long long n;
  cin >> n;

  ++n;
  int h0 = zeller(2014, 7, 23);
  long long ret = 0;
  
  long long y;
  long long cyc;
  long long block;

  for (y = 2015; y < n; y++) {
    int h = zeller(y, 7, 23);
    ret += h == h0;
    if (dp[y%400][h]) {
      cyc = y - dp[y%400][h];
      block = ret - sum[y%400][h];
      break;
    }
    dp[y%400][h] = y;
    sum[y%400][h] = ret;
  }

  if (y < n) {
    long long t = (n - y) / cyc;
    y += t * cyc;
    ret += t * block;
    
    while (y < n) {
      if (zeller(y, 7, 23) == h0)
        ++ret;
      ++y;
    }
  }
  
  cout << ret << endl;

  return 0;
}