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#include <bits/stdc++.h>
#define dbg(x) " [" << #x << ": " << (x) << "] "
using namespace std;
template<typename A, typename B>
ostream& operator<<(ostream& out, const pair<A,B>& p) {
    return out << "(" << p.first << ", " << p.second << ")";
}
template<typename T>
ostream& operator<<(ostream& out, const vector<T>& c) {
    out << "{";
    for(auto it = c.begin(); it != c.end(); it++) {
        if(it != c.begin()) out << ", ";
        out << *it;
    }
    return out << "}";
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    vector<int> v(n);
    for(int& i : v) cin >> i;
    vector<int> xx = v;
    sort(xx.begin(), xx.end());
    vector<int> mp(3001);
    for(int i = 0; i < n; i++) {
        mp[xx[i]] = i;
    }
    for(int& i : v) i = mp[i];
    vector<int> u(n);
    vector<vector<int>> c;
    int mx = 1;
    for(int i = 0; i < n; i++) {
        if(u[i]) continue;
        int j = i;
        c.push_back(vector<int>());
        do {
            u[j] = 1;
            c.back().push_back(j);
            j = v[j];
        } while(j != i);
        mx = max(mx, (int)c.back().size());
    }
    if(mx == 1) {
        cout << 0 << endl;
    } else if(mx == 2) {
        cout << 1 << endl;
        vector<int> a,b;
        for(int i = 0; i < c.size(); i++) {
            if(c[i].size() == 2) {
                a.push_back(c[i][0] + 1);
                b.push_back(c[i][1] + 1);
            }
        }
        cout << 2 * a.size() << endl;
        for(int i : a) cout << i << " ";
        reverse(b.begin(), b.end());
        for(int i = 0; i < b.size(); i++) {
            cout << b[i];
            if(i + 1 < b.size()) cout << " ";
        }
        cout << endl;
    } else {
        cout << 2 << endl;
        vector<pair<int,int>> x,y;
        for(int i = 0; i < c.size(); i++) {
            if(c[i].size() == 1) continue;
            x.push_back({c[i][c[i].size() - 2], c[i][c[i].size() - 1]});
            for(int j = 0; 2 * j + 3 < c[i].size(); j++) {
                x.push_back({c[i][j], c[i][c[i].size() - 3 - j]});
            }
            for(int j = 0; 2 * j + 2 < c[i].size(); j++) {
                y.push_back({c[i][j], c[i][c[i].size() - 2 - j]});
            }
        }
        cout << 2 * x.size() << endl;
        for(auto [a,b] : x) cout << a + 1 << " ";
        for(int i = (int)x.size() - 1; i >= 0; i--) {
            cout << x[i].second + 1;
            if(i) cout << " ";
        }
        cout << endl << 2 * y.size() << endl;
        for(auto [a,b] : y) cout << a + 1 << " ";
        for(int i = (int)y.size() - 1; i >= 0; i--) {
            cout << y[i].second + 1;
            if(i) cout << " ";
        }
        cout << endl;
    }
    return 0;
}