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//~ while (clock()<=69*CLOCKS_PER_SEC)
//~ #pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("O3")
//~ #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>

using namespace std;

using ll=long long;
using ld=long double;
using pii=pair<int, int>;
using pll=pair<ll, ll>;
using vi=vector<int>;
using vll=vector<ll>;

template<class TH> void _dbg(const char *sdbg, TH h){ cerr<<sdbg<<" = "<<h<<endl; }
#ifdef LOCAL
#define _upgrade ios_base::sync_with_stdio(0);
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__);
#else
#define _upgrade ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
#define debug(...) 98;
#define cerr if(0) cout
#endif

#define pb push_back
#define mp make_pair
#define all(x) x.begin(),x.end()
#define sz(x) ((int)(x).size())
#define fi first
#define se second

#define erase_duplicates(x) sort(all(x)), (x).resize(distance((x).begin(), unique(all(x))));

#define watch(x) cout << (#x) << " is " << (x) << endl;

#define pow2(x) ((x)*(x))
#define mod(x, m) ((((x) % (m)) + (m)) % (m))
#define max3(a, b, c) max(a, max(b, c))
#define min3(a, b, c) min(a, min(b, c))

#define REP(i, a, b) for(int i = a; i <= b; ++i)
#define REPV(i, b, a) for(int i = b; i >= a; --i)

const double m_pi = acos(-1.0);
const int int_max = 0x3f3f3f3f;
const int M7 = 1000*1000*1000+7;
const int M9 = 1000*1000*1000+9;

vector<pii> tab;
vector<int> bc;
vector<int> fw;
vector<bool> done[2];
vector<pii> moves[2];

int main() {
    _upgrade
    mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
    cout<<fixed<<setprecision(15);
    
    int n; cin>>n;
    bc.resize(n);
    fw.resize(n);
    done[0].resize(n);
    done[1].resize(n);
    REP(i, 0, n-1){
        int h;cin>>h;
        tab.pb(mp(h, i));
    }
    sort(tab.begin(), tab.end());

    REP(i, 0, n-1){
        int idx = tab[i].se;
        fw[idx] = i;
        bc[i] = idx;
    }


    auto makeSwitch = [=] (int a, int b, int doneI) {
        if(done[doneI][a] || done[doneI][b])return false;
        done[doneI][a] = true;
        done[doneI][b] = true;
        moves[doneI].pb(mp(a, b));
        int fa = fw[a];
        int fb = fw[b];
        fw[a] = fb;
        fw[b] = fa;
        bc[fb] = a;
        bc[fa] = b;
        return true;
    };


    REP(doneI, 0, 1){
        REP(i, 0, n-1) {
            if(done[doneI][i]) continue;
                int idx = i;
            while(1) {
                bool madeSwitch = false;
                int switchIdx = fw[fw[idx]];
                if(idx != switchIdx) {
                    madeSwitch = makeSwitch(idx, switchIdx, doneI);
                } else if (idx != fw[idx]) {
                    switchIdx = fw[idx];
                    madeSwitch = makeSwitch(idx, switchIdx, doneI);
                } else {
                    done[doneI][idx] = true;
                }
                idx = bc[idx];
                if(!madeSwitch)break;
            }
        }
    }

    int r = 0;
    if(sz(moves[0]))++r;
    if(sz(moves[1]))++r;

    cout << r << "\n";
    REP(i, 0, r-1) {
        cout << sz(moves[i])*2<<"\n";
        REP(j, 0, sz(moves[i])-1){
            cout << moves[i][j].fi+1 << " ";
        }
        REPV(j, sz(moves[i])-1, 0){
            cout << moves[i][j].se+1 << " ";
        }
        cout << "\n";
    }

    // REP(i, 0, n-1){
    //     if(fw[i] != i || bc[i] != i) cout << "err" << endl;
    // }




    return 0;
}




/*
    __builtin_popcount count total set bits on a given integer
    (use __builtin_popcountll for long long).

7 
5 7 6 1 2 4 3

*/