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// #pragma GCC optimize("O3")
// #pragma GCC optimize("Ofast")
// #pragma GCC optimize("unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>

// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
// using namespace __gnu_pbds;

// #define ordered_set                                                            \
//   tree<PII, null_type, less<PII>, rb_tree_tag,                                 \
//        tree_order_statistics_node_update>

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> PII;
typedef pair<ll, ll> PLL;
typedef pair<ld, ld> PLD;
typedef vector<int> VI;
typedef vector<ll> VL;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<VL> VVL;
typedef vector<VII> VVII;
typedef vector<PLL> VLL;
typedef vector<VLL> VVLL;
typedef vector<VI> VVI;
typedef vector<VL> VVL;
typedef vector<bool> VB;
typedef vector<VB> VVB;
typedef vector<string> VS;

template <class T, class G>
ostream &operator<<(ostream &os, const pair<T, G> &para) {
  os << para.first << " " << para.second;
  return os;
}
template <class T> ostream &operator<<(ostream &os, const vector<T> &vec) {
  for (const T &el : vec)
    os << el << " ";
  return os;
}
template <class T> ostream &operator<<(ostream &os, const set<T> &vec) {
  for (const T &el : vec)
    os << el << " ";
  return os;
}

#define REP(i, j) for (int i = 0; i < (j); i++)
#define REP1(i, j) for (int i = 1; i < (j); i++)
#define FOREACH(el, n) for (auto &el : n)
#define pb push_back
#define pf push_front
#define st first
#define nd second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define get_unique(x) x.erase(unique(all(x)), x.end());
#define sp ' '
#define ent '\n'

// template <class T> void print_case(int i, T &x) {
//   cout << "Case #" << i << ": " << x << ent;
// }
// void prep() {}

void TEST(int testcase_i) {
  int n;
  cin >> n;
  VI v(n + 1);
  REP(i, n) cin >> v[i + 1];

  map<int, int> pom;
  for (int i = 1; i <= n; ++i)
    pom[v[i]] = i;

  int cnter = 1;
  for (auto [el, idx] : pom)
    v[idx] = cnter++;

  VVI ANS;
  while (true) {
    VVI circles;
    VB vis(n + 1);
    for (int i = 1; i <= n; ++i) {
      int cur_len = 0;
      int cur = i;
      VI cur_circle;
      while (!vis[cur]) {
        cur_circle.pb(cur);
        vis[cur] = true;
        cur_len++;
        cur = v[cur];
      }
      if (cur_len & 1)
        cur_circle.pop_back();
      if (cur_len > 1)
        circles.pb(cur_circle);
    }

    VI ans;
    for (auto &circle : circles) {
      int siz = circle.size();
      REP(i, siz / 2) {
        ans.pb(circle.back());
        circle.pop_back();
      }
    }
    for (int i = circles.size() - 1; i >= 0; --i) {
      while (circles[i].size()) {
        ans.pb(circles[i].back());
        circles[i].pop_back();
      }
    }
    // cout << ans << ent;
    REP(i, ans.size() / 2) {
      swap(v[ans[i]], v[ans[ans.size() - 1 - i]]);
    }
    if (ans.size())
      ANS.pb(ans);
    else
      break;
  }

  cout << ANS.size() << ent;
  for (const auto &el : ANS) {
    cout << el.size() << ent;
    cout << el << ent;
  }
}

int main() {
  // ios_base::sync_with_stdio(false);
  // cin.tie(nullptr);
  // cout.tie(nullptr);

  // cout << setprecision(16) << fixed;

  // srand(time(NULL));

  // freopen("sorting.in", "r", stdin);
  // freopen("sorting.out", "w", stdout);

  // prep();

  int t = 1;
  // cin >> t;
  REP(i, t) {
    TEST(i);
  }

  return 0;
}