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#include<bits/stdc++.h>
using namespace std;
int tab[3009];
bool zaj[3009];
deque<int>A,B;
int main()
{ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    int n;
    cin>>n;
    vector<pair<int,int>>skal;
    for(int i=1;i<=n;i++)
    {
        cin>>tab[i];
        skal.push_back({tab[i],i});
    }
    sort(skal.begin(),skal.end());
    int h=0;
    for(int i=0;i<skal.size();i++)
    {
        if(i==0||skal[i-1].first!=skal[i].first)
        {
            h++;
        }
        tab[skal[i].second]=h;
    }
    for(int i=1;i<=n;i++)
    {
        if(zaj[i]==1){continue;}
        vector<int>U;
        int v=i;
        while(zaj[v]==0)
        {
            U.push_back(v);
            zaj[v]=1;
            v=tab[v];
        }
        if(U.size()==2)
        {
            A.push_front(U[0]);
            A.push_back(U[1]);
        }
        else if(U.size()>=3)
        {
            int uwu=U.size()/2;
            if(U.size()%2==0)
            {
                for(int i=0;i<uwu;i++)
                {
                    A.push_front(U[i]);
                    A.push_back(U[U.size()-i-1]);
                }
                for(int i=1;i<uwu;i++)
                {
                    B.push_front(U[i]);
                    B.push_back(U[U.size()-i]);
                }
            }
            else
            {
                for(int i=0;i<uwu;i++)
                {
                    A.push_front(U[i]);
                    A.push_back(U[U.size()-i-1]);
                }
                for(int i=1;i<=uwu;i++)
                {
                    B.push_front(U[i]);
                    B.push_back(U[U.size()-i]);
                }
            }
        }
    }
    if(A.size()==0){cout<<0<<endl;}
    else if(B.size()==0)
    {
        cout<<1<<endl;
        cout<<A.size()<<endl;
        for(int i=0;i<A.size();i++)
        {
            cout<<A[i]<<" ";
        }
        cout<<endl;
    }
    else
    {
        cout<<2<<endl;
        cout<<A.size()<<endl;
        for(int i=0;i<A.size();i++)
        {
            cout<<A[i]<<" ";
        }
        cout<<endl;
        cout<<B.size()<<endl;
        for(int i=0;i<B.size();i++)
        {
            cout<<B[i]<<" ";
        }
        cout<<endl;
    }
    return 0;
}