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#include<iostream>
#include<vector>
#include<algorithm>
#include<utility>

using namespace std;

void dfs(int i, vector<int> &A, vector<int> &B,vector<int> &C,vector<int> &N,vector<int> &L1,vector<int> &L2,vector<int> &P1,vector<int> &P2,vector<bool> &V){
    //cout << "node: " <<  i <<'\n';
    if(V[i])return;
    V[i] = true;
    if(B[i] == N[i]){
        //cout << "A\n";
        L2.push_back(C[N[i]]);
        P2.push_back(C[i]);
        V[N[i]]=true;
        return;
    }
    if(N[N[i]] == B[i]){
        //cout << "B\n";
        L1.push_back(C[B[i]]);P1.push_back(C[i]);
        L2.push_back(C[B[i]]);P2.push_back(C[N[i]]);
        V[N[i]] = true;
        V[B[i]] = true;
        return;
    }
    //cout << "C\n";
    V[N[i]]=true;
    L1.push_back(C[N[N[i]]]);P1.push_back(C[i]);
    L2.push_back(C[N[N[i]]]);P2.push_back(C[N[i]]);
    C[N[N[i]]] = C[i];
    B[N[N[i]]]=B[i];
    N[B[i]] = N[N[i]];
    dfs(B[i],A,B,C,N,L1,L2,P1,P2,V);
}

int main(){
    cin.tie(0);cout.tie(0);ios_base::sync_with_stdio(0);
    int n; cin >> n;
    vector<pair<int,int> > T(n);
    for(int i=0;i<n;i++){
        cin >> T[i].first;
        T[i].second = i;
    }
    sort(T.begin(),T.end());
    vector<int> A(n),C(n);
    for(int i=0;i<n;i++)A[T[i].second] = i;
    T.resize(0);
    for(int i=0;i<n;i++)C[A[i]] = i+1;
    // cout << "A: ";
    // for(int i=0;i<n;i++) cout << A[i] << ' ';
    // cout << '\n';
    vector<int> B(n, -1), N(n, -1);
    for(int i=0;i<n;i++){
        if(i!=A[i]){
            N[A[i]] = A[A[i]];
            B[A[A[i]]] = A[i];
        }
    }
    //cout << "B N\n";
    //for(int i=0;i<n;i++) cout << B[i] << ' ' << N[i] << '\n';
    vector<int> L1,L2,P1,P2;
    vector<bool> V(n,false);
    for(int i=0;i<n;i++){
        if(A[i]!=i)dfs(A[i],A,B,C,N,L1,L2,P1,P2,V);
    }
    reverse(P1.begin(),P1.end());
    reverse(P2.begin(),P2.end());
    L1.insert(L1.end(),P1.begin(),P1.end());
    L2.insert(L2.end(),P2.begin(),P2.end());
    if(L1.size() == 0 && L2.size() == 0)cout << 0 << '\n';
    else if(L1.size()==0){
        cout << 1 << '\n';
        cout << L2.size() << '\n';
        for(int i=0;i<L2.size();i++) cout << L2[i] << ' ';
        cout << '\n';
    }
    else{
        cout << 2 << '\n';
         cout << L1.size() << '\n';
        for(int i=0;i<L1.size();i++) cout << L1[i] << ' ';
        cout << '\n';
        cout << L2.size() << '\n';
        for(int i=0;i<L2.size();i++) cout << L2[i] << ' ';
        cout << '\n';

    }

}