#include <bits/stdc++.h>
using namespace std;
const double eps = 1e-9;
const double PI = acos(-1.0);
const int INF = 1e9 + 7;
const int N = int(2e5 + 7);
int n;
double len, add;
pair<double, double> a[5];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  scanf("%d", &n);
  len = sqrt(200 - 200.0 * cos(0.6 * PI));
  a[0] = make_pair(0.0, 10.0 * sin(0.4 * PI));
  a[3] = make_pair(10.0 * cos(0.4 * PI), 0.0);
  a[1] = make_pair(a[3].first + 10.0, 0.0);
  a[2] = make_pair(a[3].first + 5.0, a[0].second + 10.0 * cos(0.3 * PI));
  a[4] = make_pair(len, 10.0 * sin(0.4 * PI));
  printf("%d\n", n * 5 - n + 1);
  for (int i = 0; i < n; i++) {
    for (int j = i == 0 ? 0 : 1; j < 5; j++)
      printf("%.10f %.10f\n", a[j].first + add, a[j].second);
    add += len;
  }
  for (int i = 0; i < n; i++)
    printf("%d %d %d %d %d\n", 1 + i * 4, 3 + i * 4, 5 + i * 4, 2 + i * 4,
           4 + i * 4);
  for (int i = 0; i < n * 5 - n + 1; i++) printf("%d ", i + 1);
  for (int i = n * 5 - n - 3; i > 0; i -= 4) printf("%d ", i);
  return 0;
}
