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#include <bits/stdc++.h>

using namespace std;

typedef pair<int, int> pii_t;
typedef vector<pii_t> round_t;

void remap_height(vector<int>& height)
{
    vector<pair<int,int>> v(height.size());
    for (int i = 0; i < (int)height.size(); i++)
        v[i] = {height[i], i};

    sort(v.begin(), v.end());

    for (int i = 0; i < (int)v.size(); i++)
        height[v[i].second] = i;
}

vector<int> build_round(const round_t& swaps)
{
    vector<int> result(2 * swaps.size());
    for (int i = 0; i < (int)swaps.size(); i++)
    {
        result[i] = swaps[i].first;
        result[result.size()-1-i] = swaps[i].second;
    }

    return result;
}

pair<round_t, round_t> resolve_cycle(const vector<int>& cycle)
{
    round_t r1, r2;
    if (cycle.size() == 1)
        return {r1, r2};
    else if (cycle.size() == 2)
    {
        r1.push_back({cycle[0], cycle[1]});
        return {r1, r2};
    }

    // cycle.size() >= 3
    int mid = cycle.size() / 2;
    r1.push_back({cycle[mid-1], cycle[mid]});
    int left = mid-2, right = mid+1;

    while (0 <= left && right < (int)cycle.size())
    {        
        r1.push_back({cycle[left], cycle[right]});
        r2.push_back({cycle[left+1], cycle[right]});
        left--, right++;
    }
    
    if (cycle.size() % 2 == 1)
        r2.push_back({cycle.front(), cycle.back()});

    return {r1, r2};
}

vector<vector<int>> get_cycles(const vector<int>& p)
{
    vector<vector<int>> cycles;
    vector<bool> used(p.size(), false);

    for (int i = 0; i < (int)p.size(); i++)
        if (!used[i])
        {
            used[i] = true;
            vector<int> c = {i};
            while (p[c.back()] != c.front())
            {
                used[p[c.back()]] = true;
                c.push_back(p[c.back()]);
            }

            cycles.push_back(c);
        }

    return cycles;
}

int main()
{
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);

    int n; cin >> n;
    vector<int> p(n);
    for (int i = 0; i < (int)p.size(); i++)
    {
        cin >> p[i];
        p[i]--;
    }

    remap_height(p);

    vector<vector<int>> cycles = get_cycles(p);

    round_t r1, r2;
    for (const auto& c : cycles)
    {
        auto [r1_part, r2_part] = resolve_cycle(c);

        for (const auto& e : r1_part)
            r1.push_back(e);

        for (const auto& e : r2_part)
            r2.push_back(e);
    }

    if (r1.empty())
        cout << "0\n";
    else if (r2.empty())
    {   
        cout << "1\n";

        vector<int> round1 = build_round(r1);
        cout << round1.size() << "\n";
        for (const auto& e : round1)
            cout << e+1 << " ";
        cout << "\n";
    }
    else
    {
        cout << "2\n";

        vector<int> round1 = build_round(r1);
        cout << round1.size() << "\n";
        for (const auto& e : round1)
            cout << e+1 << " ";
        cout << "\n";

        vector<int> round2 = build_round(r2);
        cout << round2.size() << "\n";
        for (const auto& e : round2)
            cout << e+1 << " ";
        cout << "\n";
    }
}