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//Franciszek Witt
#include<bits/stdc++.h>
using namespace std;
#define FOR(i,l,r) for(int i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...);}(x),cerr<<'\n'
#else
#define debug(...) {}
#endif
typedef long long ll;
struct ska {
    vector<int> ve;
    void add(int x) {
        ve.emplace_back(x);
    }
    void go() {
        sort(ve.begin(), ve.end());
    }
    int get(int x) {
        return lower_bound(ve.begin(), ve.end(), x) - ve.begin() + 1;
    }
};
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >> n;
    vector<int> v(n + 1);
    ska sk;
    FOR(i, 1, n) {
        cin >> v[i];
        sk.add(v[i]);
    }
    sk.go();
    FOR(i, 1, n)
        v[i] = sk.get(v[i]);

    vector bn(n + 1, 0);
    vector ccl(0, vector<int>());
    FOR(i, 1, n) {
        if(!bn[i]) {
            ccl.resize(ccl.size() + 1);
            int ptr = i;
            while(!bn[ptr]) {
                bn[ptr] = 1;
                ccl.back().emplace_back(ptr);
                ptr = v[ptr];
            }
        }
    }

    int mxs = 0;
    for(auto &i : ccl)
        mxs = max(mxs, ssize(i));

    auto work = [&] (vector<pair<int, int>> ve) {
        vector<int> le, ri;
        for(auto [l, r] : ve) {
            le.emplace_back(l);
            ri.emplace_back(r);
        }
        reverse(ri.begin(), ri.end());
        for(auto i : ri)
            le.emplace_back(i);
        return le;
    };

    debug(v);
    debug(ccl);

    if(mxs == 1) {
        cout << 0 << endl;
    }
    else if(mxs == 2) {
        vector<pair<int, int>> vp;
        for(auto &i : ccl)
            if(ssize(i) == 2)
                vp.emplace_back(i[0], i[1]);
        auto tmp = work(vp);
        cout << 1 << endl;
        cout << ssize(tmp) << endl;
        for(auto i : tmp)
            cout << i << " ";
        cout << endl;
    }
    else {
        vector<pair<int, int>> vp0, vp1;
        for(auto &i : ccl) {
            int si = ssize(i);
            for(int j = 0; j < (si - 1) / 2; ++j)
                vp0.emplace_back(i[j], i[si - 2 - j]);
            for(int j = 0; j < si / 2; ++j)
                vp1.emplace_back(i[j], i[si - 1 - j]);
        }
        auto tmp0 = work(vp0), tmp1 = work(vp1);
        cout << 2 << endl;

        cout << ssize(tmp0) << endl;
        for(auto i : tmp0)
            cout << i << " ";
        cout << endl;

        cout << ssize(tmp1) << endl;
        for(auto i : tmp1)
            cout << i << " ";
        cout << endl;
    }
}