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#include <iostream>
#include <vector>
constexpr int maxN = 5000;
int t[maxN];
int count[maxN];
int out[maxN];
bool visited[maxN];
int vis[maxN];
std::vector<int> v;
int main()
{
	std::ios_base::sync_with_stdio(0);
	std::cin.tie(0);
	int n;
	std::cin >> n;
	for (int i = 0; i < n; ++i)
	{
		std::cin >> t[i];
		++count[t[i]];
	}
	for (int i = 1; i < maxN; ++i)
	{
		count[i] += count[i - 1];
	}
	for (int i = 0; i < n; ++i)
	{
		out[i] = --count[t[i]];
	}
	int maxsize = 0;
	for (int i = 0; i < n; ++i)
	{
		int j = i;
		int size = 0;
		while (!visited[j])
		{
			visited[j] = 1;
			++size;
			j = out[j];
			if (size == 1)
				v.push_back(j);
		}
		maxsize = std::max(maxsize, size);
	}
	int m = 0;
	int l = 1;
	while (maxsize > l)
	{
		++m;
		l *= 2;
	}
	std::cout << m << "\n";
	std::vector<int> front, end;
	for (int ij = 1; ij <= m; ++ij)
	{
		front.clear(), end.clear();
		for (int i = 0; i < v.size(); ++i)
		{
			if (out[v[i]] == v[i])
			{
				std::swap(v[i], v[v.size() - 1]);
				v.pop_back();
				--i;
				continue;
			}
			int j = out[v[i]];
			while (vis[j] != ij && vis[out[j]] != ij)
			{
				vis[j] = ij;
				vis[out[j]] = ij;
				if (out[j] == j)
				{
					std::swap(v[i], v[v.size() - 1]);
					v.pop_back();
					--i;
					break;
				}
				front.push_back(j);
				end.push_back(out[j]);
				std::swap(out[j], out[out[j]]);
				j = out[j];
			}
			v[i] = j;
		}
		std::cout << front.size() * 2 << "\n";
		for (int i = 0; i < front.size(); ++i)
			std::cout << front[i] + 1 << " ";
		for (int i = end.size() - 1; i >= 0; --i)
			std::cout << end[i] + 1 << " ";
		std::cout << "\n";
	}
}