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#include <bits/stdc++.h>

using namespace std;

int n;
vector<int> tmpv;
array<int, 3000> pos;
vector<pair<vector<int>, vector<int>>> rounds;

// void go(vector<int> &cycle, int i, int j) {
//     // cout << '.';second
//     if (i >= j) return;
//     int which = i + (j - i + 1) / 2;

//     // cout << "swapping " << cycle[i] << " with " << cycle[which] << endl;
//     rounds.back().first.push_back(cycle[i]);
//     rounds.back().second.push_back(cycle[which]);
//     go(cycle, i + 1, which - 1);
//     go(cycle, which + 1, j);
// }

bool onestep() {
    bool ok = true;
    for (int i = 1; i < n; i++) {
        if (tmpv[i] < tmpv[i - 1]) {
            ok = false;
            break;
        }
    }
    if (ok) return true;


    for (int &i: pos) i = 0;

    vector<int> perm(n);
    int which = 0;
    for (int i : tmpv) {
        perm[which++] = i;
    } 
    
    vector<vector<int>> cycles;
    for (int i = 0; i < n; i++) {
        int target = perm[i];
        if (target == -1) continue;
        cycles.emplace_back();
        while (true) {
            cycles.back().push_back(target);
            int next_target = perm[target];
            perm[target] = -1;
            if (target == i) break;
            target = next_target;
        }
    }
    // cout << cycles.size() << endl;
    // for (auto &cycle : cycles) {
    //     for (int i : cycle) cout << i + 1 << ' ';
    //     cout << endl;
    // }
    int rem_cycles = cycles.size();
    for (int i = 0; i < rem_cycles; i++) {
        auto it = cycles[i].begin(); 
        it++;
        if (it == cycles[i].end()) {
            swap(cycles[--rem_cycles], cycles[i--]);
            cycles.pop_back();
        }
    }
    // if (!rem_cycles) return;
    rounds.emplace_back();
    for (auto &cycle : cycles) {
        int i = 0, j = cycle.size() - 1;
        while (i < j) {
            rounds.back().first.push_back(cycle[i++]);
            rounds.back().second.push_back(cycle[j--]);
        }
    }
    int half = rounds.back().first.size();
    for (int i = 0; i < half; i++) {
        swap(tmpv[rounds.back().first[i]], tmpv[rounds.back().second[i]]);
    }
    return false;
}

void solve() {
    cin >> n;
    tmpv = vector<int>(n);
    for (int &i : pos) i = 0;
    for (int i = 0; i < n; i++) {
        int v;
        cin >> v;
        // tmpv.push_back(v);
        pos[--v] = i + 1; 
    }
    int which = 0;
    for (int i : pos) {
        if (i) {
            tmpv[i - 1] = which++;
        }
    }
    // for (int v : tmpv) cout << v << ' ';
    // cout << endl;
    while (!onestep());

    int ans = rounds.size();
    cout << ans << '\n';
    for (int i = 0; i < ans; i++) {
    // for (int i = ans - 1; i >= 0; i--) {
        int halfsize = rounds[i].first.size();
        cout << halfsize * 2 << '\n';
        for (auto it = rounds[i].first.begin(); it != rounds[i].first.end(); it++) {
            cout << *it + 1 << ' ';
        }
        for (auto it = rounds[i].second.rbegin(); it != rounds[i].second.rend(); it++) {
            cout << *it + 1 << ' ';
        }
        cout << '\n';
    }
    // for (int v : tmpv) cout << v << ' ';
    // cout << endl;
}

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

// #ifdef LOCAL
//     int t; cin >> t; while (t--)
// #endif

    solve();

    cout.flush();
}