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// while (clock()<=69*CLOCKS_PER_SEC)
// #pragma comment(linker, "/stack:200000000")
// #pragma GCC optimize("O3")
// #pragma GCC target ("avx2")
// #pragma GCC optimize("Ofast")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
// #pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set =
    tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

#define sim template <class c
#define ris return *this
#define dor > debug &operator<<
#define eni(x)                                                                    \
    sim > typename enable_if<sizeof dud<c>(0) x 1, debug &>::type operator<<(c i) \
    {
sim > struct rge {
    c b, e;
};
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c *x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef XOX
    ~debug()
    {
        cerr << endl;
    }
    eni(!=) cerr << boolalpha << i;
    ris;
} eni(==) ris << range(begin(i), end(i));
}
sim, class b dor(pair<b, c> d)
{
    ris << "" << d.first << " --> " << d.second << "";
}
sim dor(rge<c> d)
{
    *this << "[";
    for (auto it = d.b; it != d.e; ++it)
        *this << ", " + 2 * (it == d.b) << *it;
    ris << "]";
}
#else
    sim dor(const c &)
    {
        ris;
    }
#endif
}
;
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

#ifdef XOX
#warning Times may differ!!!
#endif

#define endl '\n'
#define pb emplace_back
#define vt vector
#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

const int nax = 1e6, mod = 1e9 + 7;

int main()
{
    cin.tie(0)->sync_with_stdio(0);
    int n;
    cin >> n;
    vt<int> v(n);
    for (auto &i : v) {
        cin >> i;
    }
    {
        vt<int> vp = v;
        sort(all(vp));
        for (int i = 0; i < n; i++) {
            v[i] = lower_bound(all(vp), v[i]) - vp.begin();
        }
    }
    debug() << imie(v);
    vt<vt<int>> cycles;
    vt<int> used(n);
    vt<vt<pii>> wyp(2);
    for (int i = 0; i < n; i++) {
        vt<int> cycle;
        int u = i;
        while (!used[u]) {
            cycle.pb(u);
            used[u] = 1;
            u = v[u];
        }
        if (sz(cycle) <= 1) {
            continue;
        }
        debug() << imie(cycle);
        auto adv = [&](int ux, int x) {
            return (ux + x + sz(cycle)) % sz(cycle);
        };
        int ii = adv(0, sz(cycle) % 2 == 0 ? 0 : -1), jj = 1;
        while (1) {
            if (ii == jj) {
                break;
            }
            wyp[0].pb(cycle[ii], cycle[jj]);
            if (adv(ii, 1) != jj) {
                wyp[1].pb(cycle[adv(ii, 1)], cycle[jj]);
            }
            if (adv(jj, 1) == ii) {
                break;
            }
            jj = adv(jj, 1);
            ii = adv(ii, -1);
        }
    }
    while (wyp.size() && wyp.back().empty()) {
        wyp.pop_back();
    }
    assert(sz(wyp) <= 2);
    cout << sz(wyp) << endl;
    debug() << imie(wyp);
    for (auto seq : wyp) {
        vt<int> left, right;
        for (auto [a, b] : seq) {
            left.pb(a);
            right.pb(b);
            swap(v[a], v[b]);
        }
        reverse(all(right));
        cout << sz(seq) * 2 << endl;
        set<int> secik;
        for (auto x : left) {
            cout << x + 1 << " ";
            secik.insert(x);
        }
        for (auto x : right) {
            cout << x + 1 << " ";
            secik.insert(x);
        }
        assert(sz(secik) == sz(seq) * 2);
        cout << endl;
    }
    debug() << imie(v);
    assert(is_sorted(all(v)));
}