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#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n;
	cin >> n;
	vector <int> v(n);
	vector <pair <int, int> > ts(n);
	for (int i = 0; i < n; i++) {
		cin >> v[i];
		ts[i] = {v[i], i};
	}
	sort(ts.begin(), ts.end());
	for (int i = 0; i < n; i++)
		ts[i].ff = i;

	vector <vector <int> > c;
	vector <bool> used(n);
	for (int i = 0; i < n; i++) {
		if (ts[i].ff != ts[i].ss && !used[ts[i].ss]) {
			c.emplace_back();
			int j = i;
			while (c.back().empty() || ts[j].ss != c.back().front()) {
				c.back().emplace_back(ts[j].ss);
				used[ts[j].ss] = 1;
				j = ts[j].ss;
			}
		}
	}
//	for (auto i : c) {
//		for (auto j : i) {
//			cout << j << " ";
//		}
//		cout << "\n";
//	}
//	return 0;

	vector <vector <int> > res(2);
	for (int i = 0; i < (int)c.size(); i++) {
		for (int j = 0; j < (int)c[i].size()/2; j++) {
			res[0].push_back(c[i][j]+1);
			res[0].push_back(c[i][c[i].size()-1-j]+1);
		}
		for (int j = 0; j < (int)(c[i].size()-1)/2; j++) {
			res[1].push_back(c[i][j]+1);
			res[1].push_back(c[i][c[i].size()-2-j]+1);
		}
	}
	


//	vector <deque <int> > res(2);
//	for (int i = 0; i < (int)c.size(); i++) {
//		for (int j = 0; j < (int)c[i].size()/2; j++) {
//			res[0].push_front(c[i][j]+1);
//			res[0].push_back(c[i][c[i].size()-1-j]+1);
//		}
//		for (int j = 0; j < (int)(c[i].size()-1)/2; j++) {
//			res[1].push_front(c[i][j]+1);
//			res[1].push_back(c[i][c[i].size()-2-j]+1);
//		}
//	}
	while (!res.empty() && res.back().empty())
		res.pop_back();
	cout << res.size() << "\n";
	for (auto i : res) {
		cout << i.size() << "\n";
		for (int j = 0; j < (int)i.size(); j+=2)
			cout << i[j] << " ";
		for (int j = (int)i.size()-1; j >= 0; j -= 2)
			cout << i[j] << " ";
		cout << "\n";
	}
}