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#include <bits/stdc++.h>
#define rep(i, a, b) for (int i = a; i <= b; i++)
#define per(i, a, b) for (int i = b; i >= a; i--)
#define cat(x) cout << #x << ": " << x << endl

using namespace std;
using ll = long long;

const int N = 3030;

vector<vector<int>> res;

int n, a[N], b[N], want[N], vis[N];

int next(int i) {
	return want[a[i]];
}

void add(vector<pair<int, int>> v) {
	if (v.empty()) return;
	for (auto [x, y] : v) swap(a[x], a[y]);
	vector<int> op;
	for (auto [x, y] : v) op.push_back(x);
	reverse(v.begin(), v.end());
	for (auto [x, y] : v) op.push_back(y);
	res.push_back(op);
}

void pairs() {
	vector<pair<int, int>> cur;
	rep(i, 1, n) {
		if (next(next(i)) != i) {
			return;
		}
		if (next(i) != i && i < next(i)) {
			cur.push_back({i, next(i)});
		}
	}
	add(cur);

	rep(i, 1, n) assert(next(i) == i);
	assert(res.size() <= 2);

	cout << res.size() << "\n";
	for (auto op : res) {
		cout << op.size() << "\n";
		for (auto x : op) {
			cout << x << " ";
		}
		cout << "\n";
	}
	exit(0);
}

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

	cin >> n;
	rep(i, 1, n) cin >> a[i];

	rep(i, 1, n) b[i] = a[i];
	sort(b + 1, b + n + 1);
	rep(i, 1, n) want[b[i]] = i;

	pairs();

	vector<pair<int, int>> cur;
	rep(i, 1, n) {
		if (vis[i]) continue;
		vector<int> v;
		int x = i;
		while (!vis[x]) {
			vis[x] = 1;
			v.push_back(x);
			x = next(x);
		}

		for (int i = 1; i < int(v.size()) - i; i++) {
			cur.push_back({v[i], v[v.size() - i]});
		}
	}

	add(cur);
	pairs();
	assert(0);

	return 0;
}