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#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
#define print(g1,g2) \
cout << g1.size() + g2.size() << "\n"; \
for(int i = 0; i < g1.size(); i++) cout <<  g1[i] + 1 << " "; \
for(int i = g2.size() - 1; i >= 0; i--)cout << g2[i] + 1 << " "; \
cout << "\n";
int t[4010],temp[4010],a[4010];
bool vis[4010];
vector <int> a1,a2,b1,b2;
int main()
{
    ios_base :: sync_with_stdio(0);
    int n; cin >> n;
    for(int i = 0; i < n; i++){
        cin >> t[i];
        temp[i] = t[i];
    }
    sort(temp,temp +n);
    for(int i = 0; i < n; i++){
        a[temp[i]] = i;
    }
    for(int i = 0; i < n; i++){
        if(a[t[i]] != i && !vis[i] && !vis[a[t[i]]]){
            a1.push_back(i);
            b1.push_back(a[t[i]]);
            vis[i] = vis[a[t[i]]] = 1;
            swap(t[i],t[a[t[i]]]);
        }
    }
    for(int i = 0; i < n; i++){
        vis[i] = 0;
    }
    for(int i = 0; i < n; i++){
        if(a[t[i]] != i && !vis[i] && !vis[a[t[i]]]){
            a2.push_back(i);
            b2.push_back(a[t[i]]);
            vis[i] = vis[a[t[i]]] = 1;
        }
    }
    if(a2.size()){
        cout << 2 << "\n";
        print(a1,b1);
        print(a2,b2);
    }
    else if(a1.size()){
        cout << 1 << "\n";
        print(a1,b1);
    }
    else{
        cout << 0 << "\n";
    }


}