#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  long double l =
      sqrt(100.0 + 100.0 - 2 * 100.0 * cos(acos(-1.0) * 108.0 / 180.0));
  long double h =
      sqrt(100.0 -
           (100.0 + 100.0 - 2 * 100.0 * cos(acos(-1.0) * 108.0 / 180.0)) / 4.0);
  long double l2 = l / 2 - 5.0;
  long double h2 = sqrt(100.0 - l2 * l2);
  long double x0, y0;
  x0 = -499.0;
  y0 = 0.0;
  cout << 5 + (n - 1) * 4 << endl;
  vector<vector<pair<long double, long double> > > stars(n);
  for (int i = 0; i < n; ++i) {
    stars[i].push_back(make_pair(x0, y0));
    stars[i].push_back(make_pair(x0 + l / 2.0, y0 + h));
    stars[i].push_back(make_pair(x0 + l, y0));
    stars[i].push_back(make_pair(x0 + l2 + 10.0, y0 - h2));
    stars[i].push_back(make_pair(x0 + l2, y0 - h2));
    x0 = stars[i][2].first;
    y0 = stars[i][2].second;
  }
  cout << fixed << setprecision(10) << stars[0][0].first << " "
       << stars[0][0].second << endl;
  for (int i = 0; i < stars.size(); ++i)
    for (int j = 1; j < 5; ++j)
      cout << fixed << setprecision(10) << stars[i][j].first << " "
           << stars[i][j].second << endl;
  cout << 1 << " " << 2 << " " << 3 << " " << 4 << " " << 5 << endl;
  int cur = 3;
  for (int i = 1; i < n; ++i) {
    cout << cur << " " << cur + 3 << " " << cur + 4 << " " << cur + 5 << " "
         << cur + 6 << endl;
    cur += 4;
  }
  cout << 1 << " ";
  cur = 3;
  for (int i = 0; i < n; ++i) {
    cout << cur << " ";
    cur += 4;
  }
  cur -= 4;
  for (int i = 0; i < n; ++i) {
    cout << cur + 2 << " " << cur - 1 << " " << cur + 1 << " ";
    if (cur != 3)
      cout << cur - 4 << " ";
    else
      cout << 1;
    cur -= 4;
  }
}
