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

int n;
vector <int> a;
vector <bool> visited;

inline bool sorted()
{
	for(int i=0; i<n; ++i)
		if(a[i]!=i)
			return 0;
	return 1;
}

int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	
	cin>>n;
	
	set <int> s;
	unordered_map <int, int> nr;
	
	a.resize(n);
	visited.resize(n);
	for(int i=0; i<n; ++i)
	{
		cin>>a[i];
		s.insert(a[i]);
	}
	
	int curr=0;
	for(int x : s)
	{
		nr[x]=curr;
		++curr;
	}
	
	for(int i=0; i<n; ++i)
		a[i]=nr[a[i]];
	
	if(sorted())
	{
		cout<<"0\n";
		return 0;
	}
	
	bool one_move=1;
	for(int i=0; i<n; ++i)
	{
		if(a[a[i]]!=i)
		{
			one_move=0;
			break;
		}
	}
	
	if(one_move)
	{
		cout<<"1\n";
		
		deque <int> ans;
		for(int i=0; i<n; ++i)
		{
			if(a[i]<i)
			{
				ans.push_front(a[i]);
				ans.push_back(i);
			}
		}
		
		cout<<ans.size()<<"\n";
		while(!ans.empty())
		{
			cout<<ans.front()+1<<" ";
			ans.pop_front();
		}
		cout<<"\n";
		return 0;
	}
	
	cout<<"2\n";
	
	deque <int> ans;
	
	for(int i=0; i<n; ++i)
	{
		if(visited[i])
			continue;
		
		visited[i]=1;
		
		deque <int> cycle;
		
		cycle.push_back(i);
		int x=i;
		while(a[x]!=i)
		{
			x=a[x];
			cycle.push_back(x);
			visited[x]=1;
		}
		
		if(cycle.size()<2)
			continue;
		
		while(cycle.size()>=2)
		{
			ans.push_front(cycle.front());
			ans.push_back(cycle.back());
			
			swap(a[cycle.front()], a[cycle.back()]);
			
			cycle.pop_front();
			cycle.pop_back();
		}
	}
	
	cout<<ans.size()<<"\n";
	while(!ans.empty())
	{
		cout<<ans.front()+1<<" ";
		ans.pop_front();
	}
	cout<<"\n";
	
	ans.clear();
	for(int i=0; i<n; ++i)
	{
		if(a[i]<i)
		{
			ans.push_front(a[i]);
			ans.push_back(i);
		}
	}
	
	cout<<ans.size()<<"\n";
	while(!ans.empty())
	{
		cout<<ans.front()+1<<" ";
		ans.pop_front();
	}
	cout<<"\n";
	return 0;
}

/*
6
3 4 5 6 2 1
*/