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#include <bits/stdc++.h>

using namespace std;
#define PB push_back
#define LL long long
#define int LL
#define FOR(i,a,b) for (int i = (a); i <= (b); i++)
#define FORD(i,a,b) for (int i = (a); i >= (b); i--)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define st first
#define nd second
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())
#define VI vector<int>
#define PII pair<int,int>
#define LD long double


template<class T> ostream &operator<<(ostream &os, vector<T> V){
    os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]";
}
template<class T, size_t N> ostream &operator<<(ostream &os, array<T, N> V){
    os<<"[";for(auto vv:V)os<<vv<<",";return os<<"]";
}

template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
    return os << "(" << P.st << "," << P.nd << ")";
}


template<class C> void mini(C& a4, C b4) { a4 = min(a4, b4); }
template<class C> void maxi(C& a4, C b4) { a4 = max(a4, b4); }

template<class TH> void _dbg(const char *sdbg, TH h){cerr<<sdbg<<"="<<h<<"\n";}
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
    while(*sdbg!=',')cerr<<*sdbg++;cerr<<"="<<h<<","; _dbg(sdbg+1, a...);
}


#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout << fixed << setprecision(11);
    cerr << fixed << setprecision(6);
    int n;
    cin >> n;
    VI v(n);
    REP(i, n){
        cin >> v[i];
    }

    vector<PII> w(n);
    REP(i, n){
        w[i] = {v[i], i};
    }
    sort(ALL(w));

    REP(i, n){
        int idx = w[i].second;
        v[idx] = i;
    }
    VI q = v;

    debug(v);
    vector<deque<int>> rounds(2);
    vector<vector<int>> cycles;
    // get all permutation cycles
    REP(i, n){
        if(v[i] == -1) continue;
        int cur = i;
        vector<int> cycle;
        while(v[cur] != -1){
            cycle.PB(cur);
            int nxt = v[cur];
            v[cur] = -1;
            cur = nxt;
        }
        cycles.PB(cycle);
    }
    v = q;
    for(auto cycle: cycles){
        if(SZ(cycle) == 1){
            continue;
        }
        if(SZ(cycle) == 2){
            rounds[0].PB(cycle[0]);
            rounds[0].push_front(cycle[1]);
            swap(v[cycle[0]], v[cycle[1]]);
            continue;
        }
        debug(cycle);
        for(int i = 1, j = SZ(cycle) - 1; i < j; i++, j--){
            rounds[0].PB(cycle[i]);
            rounds[0].push_front(cycle[j]);
            swap(v[cycle[i]], v[cycle[j]]);
        }
    }
    // find cycles in v
    cycles.clear();
    REP(i, n){
        if(v[i] == -1) continue;
        int cur = i;
        vector<int> cycle;
        while(v[cur] != -1){
            cycle.PB(cur);
            int nxt = v[cur];
            v[cur] = -1;
            cur = nxt;
        }
        cycles.PB(cycle);
    }
    for(auto cycle: cycles){
        if(SZ(cycle) == 1){
            continue;
        }
        if(SZ(cycle) == 2){
            rounds[1].PB(cycle[0]);
            rounds[1].push_front(cycle[1]);
            continue;
        }
        assert(false);
    }
    while(rounds.size() && rounds.back().empty()){
        rounds.pop_back();
    }
    cout << SZ(rounds) << "\n";
    for(auto r: rounds){
        cout << SZ(r) << "\n";
        for(auto x: r){
            cout << x + 1<< " ";
        }
        cout << "\n";
    }
}