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#include <bits/stdc++.h>
#include <random>
#define ll long long int
#define pb push_back
#define st first
#define nd second
#define pii pair<int,int>
#define mp make_pair
#define pll pair<long long,long long>
#define ld long double
#define ull unsigned long long
#define mt make_tuple

using namespace std;

const int nax = 3005;
int a[nax];
bool vis[nax];
int n;

void solve(){
    cin >> n;
    for(int i=1;i<=n;i++) cin >> a[i];
    vector<int> uni;
    for(int i=1;i<=n;i++) uni.pb(a[i]);
    sort(uni.begin(), uni.end());
    for(int i=1;i<=n;i++){
        a[i] = (int)(lower_bound(uni.begin(), uni.end(), a[i]) - uni.begin()) + 1;
    }

    vector<vector<int> > cycles;
    int mx = 0;

    for(int i=1;i<=n;i++){
        if(!vis[i]){
            vector<int> cur;
            vis[i] = true;
            int tmp = a[i];
            cur.pb(i);
            while(!vis[tmp]){
                vis[tmp] = true;
                cur.pb(tmp);
                tmp = a[tmp];
            }
            cycles.pb(cur);
            mx = max(mx, (int)cur.size());
        }
    }

    vector<vector<int> > ans;
    if(mx > 2){
        deque<int> L, R;
        for(auto cur : cycles){
            if((int)cur.size() <= 2) continue;
            int l = 0;
            int r = (int)cur.size() - 1;
            int sz = cur.size();
            while(l < r){
                L.pb(cur[l + 1]);
                R.push_front(cur[(r + 1) % sz]);
                int p1 = cur[l + 1];
                int p2 = cur[(r + 1) % sz];
                swap(a[p1], a[p2]);
                l++; r--;
            }
        }
        vector<int> cur;
        for(int x : L) cur.pb(x);
        for(int x : R) cur.pb(x);
        if(cur.size()) ans.pb(cur);
    }

    deque<int> L, R;
    for(int i=1;i<=n;i++) vis[i] = false;
    for(int i=1;i<=n;i++){
        if(!vis[i] && a[i] != i){
            vis[i] = true;
            vis[a[i]] = true;
            int p1 = i;
            int p2 = a[i];
            L.pb(p1);
            R.push_front(p2);
            swap(a[p1], a[p2]);
        }
    }

    vector<int> cur;
    for(int x : L) cur.pb(x);
    for(int x : R) cur.pb(x);
    if(cur.size()) ans.pb(cur);
    cout << ans.size() << "\n";
    for(auto x : ans){
        cout << x.size() << "\n";
        for(auto y : x) cout << y << " ";
        cout << "\n";
    }
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);

    int tt = 1;
    // cin >> tt;
    while(tt--) solve();

    return 0;
}