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//: Potyczki Algorytmiczne 2022
// FOT
#include <algorithm>
#include <cstdio>
#include <vector>
#include <deque>
#include <cstddef>
#include <utility>

int main()
{
    int n{};
    std::scanf("%d", &n);

    std::vector<int> h(n);

    for (int i = 0; i < n; ++i)
    {
        std::scanf("%d", &h[i]);
    }

    std::vector<int> sorted(h);
    std::sort(sorted.begin(), sorted.end());

    std::vector<int> used(n);

    int round{ 1 };
    bool changed{};
    std::vector<std::deque<int>> swapsL{}, swapsR{};
    do
    {
        changed = false;
        swapsL.push_back({});
        swapsR.push_back({});

        for (int i = 0; i < n; ++i)
        {
            if (h[i] != sorted[i])
            {
                auto it{ std::lower_bound(sorted.begin(), sorted.end(), h[i]) };
                std::size_t index{ it - sorted.begin() };
                if (h[index] == sorted[i])
                {
                    swapsL.back().push_back(i + 1);
                    swapsR.back().push_front(index + 1);
                    std::swap(h[i], h[index]);
                    used[i] = used[index] = round;
                    changed = true;
                }
            }
        }

        for (int i = 0; i < n; ++i)
        {
            if (h[i] != sorted[i])
            {
                auto it{ std::lower_bound(sorted.begin(), sorted.end(), h[i]) };
                std::size_t index{ it - sorted.begin() };
                if ((used[i] < round) && (used[index] < round))
                {
                    swapsL.back().push_back(i + 1);
                    swapsR.back().push_front(index + 1);
                    used[i] = used[index] = round;
                    std::swap(h[i], h[index]);
                    changed = true;
                }
            }
        }
        ++round;
    }
    while (changed);

    swapsL.pop_back();
    swapsR.pop_back();

    const std::size_t rounds{ swapsL.size() };
    std::printf("%lu\n", rounds);
    for (std::size_t i = 0; i < rounds; ++i)
    {
        std::printf("%lu\n", swapsL[i].size() * 2);
        for (int swap : swapsL[i])
        {
            std::printf("%d ", swap);
        }
        for (int swap : swapsR[i])
        {
            std::printf("%d ", swap);
        }
        std::printf("\n");
    }
}