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//GRT_2018
#include <bits/stdc++.h>
#define PB push_back
#define ST first
#define ND second
#define all(x) x.begin(), x.end()
//mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

using namespace std;

using ll = long long;
using pi = pair<int,int>;
using vi = vector<int>;

const int nax = 3000 + 10;
int n;
pi h[nax];
int p[nax];
bool vis[nax];

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> h[i].ST;
		h[i].ND = i;
	}
	sort(h, h + n);
	for (int i = 0; i < n; ++i) {
		p[h[i].ND] = i;
	}
	vector<vi>cycles;
	int mx = -1;
	for (int i = 0; i < n; ++i) {
		if (!vis[i]) {
			int j = i;
			vis[j] = true;
			vi cur = {i};
			while (!vis[p[j]]) {
				vis[p[j]] = true;
				cur.PB(p[j]);
				j = p[j];
			}
			mx = max(mx, (int)cur.size());
			cycles.PB(cur);
		}
	}
	if (mx == 1) {
		cout << "0";
		return 0;
	} else if (mx == 2) {
		cout << "1\n";
		vi l = {}, r = {};
		for (auto v : cycles) {
			if ((int)v.size() == 2) {
				l.PB(v[0]);
				r.PB(v[1]);
			}
		}
		reverse(all(r));
		cout << (int)l.size() * 2 << "\n";
		for (int x : l) cout << x + 1 << " ";
		for (int x : r) cout << x + 1 << " ";
		return 0;
	}
	cout << "2\n";
	vi l = {}, r = {};
	for (auto v : cycles) {
		if ((int)v.size() > 2) {
			int a = 1, b = (int)v.size() - 1;
			while (a < b) {
				l.PB(v[a]);
				r.PB(v[b]);
				swap(p[v[a]], p[v[b]]);
				a++;
				b--;
			}
		}
	}
	reverse(all(r));
	cout << 2 * (int)l.size() << "\n";
	for (int x : l) cout << x + 1 << " ";
	for (int x : r) cout << x + 1 << " ";
	cout << "\n";
	cycles.clear();
	for (int i = 0; i < n; ++i) vis[i] = false;
	for (int i = 0; i < n; ++i) {
		if (!vis[i]) {
			int j = i;
			vis[j] = true;
			vi cur = {i};
			while (!vis[p[j]]) {
				vis[p[j]] = true;
				cur.PB(p[j]);
				j = p[j];
			}
			mx = max(mx, (int)cur.size());
			cycles.PB(cur);
		}
	}
	l.clear(); r.clear();
	for (auto v : cycles) {
		if ((int)v.size() == 2) {
			l.PB(v[0]);
			r.PB(v[1]);
		}
	}
	cout << 2 * (int)l.size() << "\n";
	reverse(all(r));
	for (int x : l) cout << x + 1 << " ";
	for (int x : r) cout << x + 1 << " ";
}