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#include <bits/stdc++.h>
using namespace std;

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	
	int n;
	cin >> n;
	
	vector<int> a(n);
	map<int, int> scale;
	for (int i = 0; i < n; i++) {
		cin >> a[i];
		scale[a[i]];
	}
	
	int last_value = 0;
	for (auto& [key, value] : scale) {
		value = last_value++;
	}
	for (int i = 0; i < n; i++) {
		a[i] = scale[a[i]];
	}
	
	vector<vector<pair<int, int>>> result;
	
	vector<bool> visited(n);
	for (int i = 0; i < n; i++) {
		if (!visited[i]) {
			vector<int> cycle;
			int curr = i;
			do {
				visited[curr] = true;
				cycle.emplace_back(curr);
				curr = a[curr];
			} while (curr != i);
			
			if ((int) cycle.size() == 2) {
				if ((int) result.size() < 1) {
					result.resize(1);
				}
				
				result[0].emplace_back(cycle[0], cycle[1]);
			}
			else if ((int) cycle.size() > 2) {
				if ((int) result.size() < 2) {
					result.resize(2);
				}
				
				for (int j = 0; j < (int) cycle.size() / 2; j++) {
					result[0].emplace_back(cycle[j], cycle[cycle.size() - 1 - j]);
				}
				for (int j = 1; j < (int) (cycle.size() + 1) / 2; j++) {
					result[1].emplace_back(cycle[j], cycle[cycle.size() - j]);
				}
			}
		}
	}
	
	cout << result.size() << '\n';
	for (auto vec : result) {
		cout << vec.size() * 2 << '\n';
		for (int i = 0; i < (int) vec.size(); i++) {
			cout << vec[i].first + 1 << ' ';
		}
		for (int i = vec.size() - 1; i >= 0; i--) {
			cout << vec[i].second + 1 << (i == 0 ? '\n' : ' ');
		}
	}
	
	return 0;
}