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#include <bits/stdc++.h>

using namespace std;

#define pii pair<int, int>

const int N = 3e3+1;

int n, h[N], x[N];
bool vis[N], us[N];

vector<pii> mv[3];

void solve(vector<int> c) {
    if (c.size() <= 1) return;
    if (c.size() == 2) {
        mv[1].push_back({c[0], c[1]});
        swap(h[c[0]], h[c[1]]);
        return;
    }
    int sz=c.size();

    for (int i=0; i<sz/2; ++i) {
        if (h[c[i]] == c[i]) continue;
        mv[1].push_back({c[i], c[sz-i-1]});
        swap(h[c[i]], h[c[sz-i-1]]);
    }

    for (int i=0; i<sz; ++i) {
        if (h[c[i]] == c[i]) continue;
        mv[2].push_back({c[i], h[c[i]]});
        swap(h[c[i]], h[h[c[i]]]);
    }
} 

vector<int> cyc;
void dfs(int v) {
    vis[v]=true; cyc.push_back(v);
    if (!vis[h[v]]) dfs(h[v]);
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    cin>>n;

    set<int> s;
    for (int i=1; i<=n; ++i) {
        cin>>h[i]; s.insert(h[i]);
    }

    int i=1;
    for (auto u : s) x[u]=i++;
    for (int i=1; i<=n; ++i) h[i]=x[h[i]];

    for (int i=1; i<=n; ++i) {
        if (vis[i]) continue;
        dfs(i); solve(cyc);
        cyc.clear();
    }

    if (mv[1].empty()) {
        assert(mv[2].empty());
        cout<<0<<"\n";
        return 0;
    }

    if (mv[2].empty()) cout<<1<<"\n";
    else cout<<2<<"\n";

    for (int i=1; i<=2; ++i) {
        vector<int> res;
        for (auto u : mv[i]) res.push_back(u.first);
        reverse(mv[i].begin(), mv[i].end());
        for (auto u : mv[i]) res.push_back(u.second);
        if (res.empty()) break;

        cout<<res.size()<<"\n";
        for (auto u : res) cout<<u<<" ";
        cout<<"\n";
    }
}