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#include <bits/stdc++.h>
using namespace std;
const int NMAX = 3e3;
int n, h[NMAX + 7];
vector<pair<int, int>> zam[10];
int ans(vector<int> t) {
    int s = t.size();
    if (s == 2) {
        zam[1].push_back({t[0], t[1]});
        return 1;
    }
    vector<int> late;
    for (int i = 0; i < s; i++) late.push_back(i);
    for (int i = 0; i < s - 1; i += 2) {
        swap(late[i], late[i + 1]);
    }
    vector<pair<int, int>> memember;
    for (int i = 1; i < s - 1; i += 2) {
        memember.push_back({late[i], late[i + 1]});
        swap(late[i], late[i + 1]);
    }
    vector<int> present;
    int j = 0;
    int odn = late[j];
    do {
        present.push_back(late[j]);
        j = late[j];
    } while (late[j] != odn);
    reverse(present.begin(), present.end());
    // vector<pair<int, int>> _next;
    // for (int i = 0; i < s; i++){
    //     _next.push_back({t[present[i]], present[i]});
    // }
    for (auto &[a, b] : memember) {
        int i = 0, j = 0;
        for (int x = 0; x < s; x++) {
            if (present[x] == b) {
                j = x;
                break;
            }
        }
        for (int x = 0; x < s; x++) {
            if (present[x] == a) {
                i = x;
                break;
            }
        }
        zam[1].push_back({t[i], t[j]});
        swap(present[i], present[j]);
    }
    for (int i = 0; i < s; i++) {
        if (present[i] & 1) {
            for (int j = 0; j < s; j++) {
                if (present[j] == present[i] - 1) {
                    zam[2].push_back({t[i], t[j]});
                    break;
                }
            }
        }
    }
    return 2;
}
int go() {
    vector<pair<int, int>> t;
    for (int i = 0; i < n; i++) {
        t.push_back(make_pair(h[i], i));
    }
    sort(t.begin(), t.end());
    int licznik = 0;
    vector<int> temp;
    for (int i = 0; i < n; i++) {
        if (t[i].first == -1) continue;
        int j = i;
        while (t[j].first != -1) {
            temp.push_back(j + 1);
            t[j].first = -1;
            j = t[j].second;
        }
        if (temp.size() <= 1){
            temp.clear();
            continue;
        }
        licznik = max(ans(temp), licznik);
        temp.clear();
    }
    return licznik;
}
int32_t main() {
    ios_base::sync_with_stdio(0);
    cout.tie(0);
    cin.tie(0);
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> h[i];
    }
    int m = go();
    cout << m << "\n";
    for (int i = 1; i <= m; i++) {
        cout << zam[i].size() * 2 << "\n";
        for (int j = 0; j < zam[i].size(); j++) cout << zam[i][j].first << " ";
        for (int j = zam[i].size() - 1; j >= 0; j--) cout << zam[i][j].second << " ";
        cout << "\n";
    }
    return 0;
}
// DAWID PAWELEC