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#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> PII;

int arr[3005];
int vis[3005];
vector<int> resb[2];
vector<int> rese[2];
int res = 0;

void solve(vector<int> cycle){
    if(cycle.size() == 1) return;
    if(cycle.size() == 2){
        resb[0].push_back(cycle[0]);
        rese[0].push_back(cycle[1]);
        res = max(res, 1);
    }
    else{
        res = max(res, 2);
        for(int l=0, r=cycle.size()-1; l<r; l++, r--){
            resb[0].push_back(cycle[l]);
            rese[0].push_back(cycle[r]);
        }
        for(int l=1, r=cycle.size()-1; l<r; l++, r--){
            resb[1].push_back(cycle[l]);
            rese[1].push_back(cycle[r]);
        }
    }
}   

int main(){
    ios_base::sync_with_stdio(0);
    int n;
    cin>>n;
    vector<PII> P;
    for(int i=1;i<=n;i++){
        int a;
        cin>>a;
        P.push_back({a,i});
    }
    sort(P.begin(), P.end());
    for(int i=0;i<n;i++) arr[P[i].second] = i+1;

    for(int i=1;i<=n;i++){
        if(vis[i]) continue;
        vector<int> cycle;
        vis[i] = 1;
        int v = i;
        cycle.push_back(v);
        v = arr[v];
        while(!vis[v]){
            cycle.push_back(v);
            vis[v] = 1;
            v = arr[v];
        }
        solve(cycle);
    }

    cout<<res<<endl;
    for(int i=0;i<res;i++){
        cout<<resb[i].size()+rese[i].size()<<endl;
        reverse(rese[i].begin(), rese[i].end());
        for(int u: resb[i]) cout<<u<<" ";
        for(int u: rese[i]) cout<<u<<" ";
        cout<<endl;
    }
}