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

#ifdef DEBUG
#include "debug.h"
#else
#define debug(...) ;
#endif

#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)

#define rep(i, n) for (int i = 0; i < (n); ++i)
#define repp(i, n, m) for (int i = (n); i < (m); ++i)

#define repr(i, n) for (int i = (n) - 1; i >= 0; --i)
#define reppr(i, n, m) for (int i = (m) - 1; i >= (n); --i)

using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using pi = pair<int, int>;
using pll = pair<ll, ll>;

template <typename T, typename V> void mini(T& a, V b) {if (b < a) a = b; }
template <typename T, typename V> void maxi(T& a, V b) {if (b > a) a = b; }

void solve() {
    int n;
    cin >> n;
    vi v(n);
    for (int &i : v) cin >> i;

    map<int, int> mp;

    for (int i : v) mp[i] = 1;

    int sofar = 0;
    for (auto& i : mp) i.second = sofar++;

    for (int &i : v) i = mp[i];

    vector<deque<int>> ans;

    while (true) {
        deque<int> layer;
        vector<bool> used(n);

        debug(v);

        for (int i = 0; i < n; ++i) {
            if (v[i] == i || used[i])
                continue;

            vi perm;

            int j = i;
            do {
                perm.push_back(j);
                used[j] = true;
                j = v[j];
            } while (j != i);

            for (int kl = 0, kr = perm.size() - 1; kl < kr; ++kl, --kr) {
                swap(v[perm[kl]], v[perm[kr]]);
                layer.push_back(perm[kl]);
                layer.push_front(perm[kr]);
            }
        }

        if (layer.empty())
            break;
        debug(layer);
        ans.emplace_back(move(layer));
    }

    assert(ans.size() <= 2);

    cout << ans.size() << '\n';
    for (auto &d : ans) {
        cout << d.size() << '\n';
        for (int i : d) cout << i+1 << ' ';
        cout << '\n';
    }
}

int main() {
#ifndef DEBUG
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
#endif
    int z = 1;
    // scanf("%d", &z);
    while (z--)
        solve();
    return 0;
}