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#include <bits/stdc++.h>
 
using namespace std;
 
#define endl '\n'
#define L long long
#define MP make_pair
#define REP(i, n) for(int i = 0; i < n; ++i)
#define REPR(i, n) for(int i = n - 1; i >= 0; --i)
#define FOR(i, a, b) for(int i = a; i < b; ++i)
#define FORR(i, a, b) for(int i = b - 1; i >= a; --i)
#define EB emplace_back
#define ST first
#define ND second
#define S size
#define RS resize
 
template<class T> using P = pair<T, T>;
template<class T> using V = vector<T>;

bool is_sorted(V<int>& v) {
    REP(i, (int)v.size() - 1) {
        if (v[i] >= v[i + 1]) {
            return false;
        }
    }
    return true;
}

V<int> scale(V<int>& v) {
    V<int> res;
    for (int x : v) {
        int c = 0;
        for (int y : v) {
            if (y < x) {
                c++;
            }
        }
        res.EB(c);
    }
    return res;
}
 
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
 
    int n;
    cin >> n;
    V<int> h(n);
    REP(i, n) {
        cin >> h[i];
    }

    h = scale(h);

    if (is_sorted(h)) {
        cout << 0;
        return 0;
    }

    V<V<int>> cycles;
    V<bool> vis(n);
    REP(i, n) {
        if (vis[i]) {
            continue;
        }

        V<int> new_cycle;
        int v = i;

        while (!vis[v]) {
            new_cycle.EB(v);
            vis[v] = true;
            v = h[v];
        }

        cycles.EB(new_cycle);
    }

    V<int> p1, p2, s1, s2;
    for (auto& c : cycles) {
        int r = (int)c.size();
        if (r == 1) {
            continue;
        }
        else if (r == 2) {
            p1.EB(c[0]);
            s1.EB(c[1]);
        }
        else {
            REP(i, r / 2) {
                p1.EB(c[i]);
                s1.EB(c[r - i - 1]);
            }
            REP(i, (r - 1) / 2) {
                p2.EB(c[i + 1]);
                s2.EB(c[r - i - 1]);
            }
        }
    }

    reverse(s1.begin(), s1.end());
    reverse(s2.begin(), s2.end());
    p1.insert(p1.end(), s1.begin(), s1.end());
    p2.insert(p2.end(), s2.begin(), s2.end());
    int r1 = (int)p1.size();
    int r2 = (int)p2.size();
    if (r2 == 0) {
        cout << "1\n" << r1 << '\n';
        for (int x : p1) {
            cout << x + 1 << ' ';
        }
    }
    else {
        cout << "2\n" << r1 << '\n';
        for (int x : p1) {
            cout << x + 1 << ' ';
        }
        cout << '\n' << r2 << '\n';
        for (int x : p2) {
            cout << x + 1 << ' ';
        }
    }
}

// g++ -std=c++17 -Wall -Wextra -Wshadow -Wconversion -D_GLIBCXX_DEBUG fot.cpp -o fot