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

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int n;
  cin >> n;

  auto f = [n](int x) {
    int res = 0;
    for (int i = 2; i <= n; i++)
      res += x % i;
    return res;
  };

  mt19937 rng(12390);

  int mx = 0;
  int B = max(1, 250000 / n);
  for (int it = 0; it < B; it++) {
    int x = rng() % (n * n), y = x;

    int c = 0;
    do {
      x = f(x);
      y = f(f(y));
      ++c;
    } while (x != y);

    int ans = 0;
    do {
      y = f(y);
      ++ans;
    } while (y != x);
    mx = max(mx, ans);
    // cerr << "c = " << c << endl;
    // cerr << "ans = " << ans << endl;
  }

  cout << mx << '\n';
  // cout << "ans = " << ans << endl;
}