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#include "bits/stdc++.h" // Tomasz Nowak
using namespace std;     // University of Warsaw
using LL = long long;
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define REP(i, n) FOR(i, 0, (n) - 1)
#define ssize(x) int(x.size())
template<class A, class B> auto& operator<<(ostream &o, pair<A, B> p) {
	return o << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) {
	o << '{'; int i = 0; for(auto e : x) o << (", ")+2*!i++ << e; return o << '}';
}
#ifdef DEBUG
#define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n'
#else
#define debug(...) {}
#endif

int main() {
	cin.tie(0)->sync_with_stdio(0);

	int n;
	cin >> n;
	vector<int> h(n);
	for(int &hi : h)
		cin >> hi;

	vector<pair<int, int>> sorted(n);
	REP(i, n)
		sorted[i] = {h[i], i};
	sort(sorted.begin(), sorted.end());
	REP(i, n)
		h[sorted[i].second] = i;
	debug(n, h);

	vector<deque<int>> out = {{}, {}};
	vector<bool> visited(n, false);
	REP(start, n)
		if(not visited[start]) {
			vector<int> cycle;
			function<void (int)> dfs = [&](int v) {
				visited[v] = true;
				cycle.emplace_back(v);
				if(not visited[h[v]])
					dfs(h[v]);
			};
			dfs(start);
			debug(cycle);

			auto add = [&](int lvl, int i, int j) {
				out[lvl].emplace_back(i);
				out[lvl].emplace_front(j);
				swap(h[i], h[j]);
			};

			if(ssize(cycle) == 1)
				continue;
			else if(ssize(cycle) == 2)
				add(0, cycle[0], cycle[1]);
			else {
				REP(i, (ssize(cycle) - 1) / 2)
					add(0, cycle[i], cycle[ssize(cycle) - 2 - i]);
				REP(i, ssize(cycle) / 2)
					add(1, cycle[i], cycle[ssize(cycle) - 1 - i]);
			}
			debug(h);
		}
	while(not out.empty() and out.back().empty())
		out.pop_back();
	cout << ssize(out) << '\n';
#ifndef LOCAL
	for(auto ids : out) {
		cout << ssize(ids) << '\n';
		for(int i : ids)
			cout << i + 1 << ' ';
		cout << '\n';
	}
#endif
}