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//#pragma GCC optimize("O3")
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include <bits/stdc++.h>
using namespace std;
namespace debug { template <class c> struct rge { c b, e; }; template <class c> rge<c> range(c i, c j) { return rge<c>{i, j}; } template <class c> char spk(...); template <class c> auto spk(c* a) -> decltype(cerr << *a, 0); struct stream { ~stream() { cerr << endl; } template <class c> typename enable_if <sizeof spk<c>(0) != 1, stream&>::type operator<<(c i) { cerr << boolalpha << i; return *this; } template <class c> typename enable_if <sizeof spk<c>(0) == 1, stream&>::type operator<<(c i) { return *this << range(begin(i), end(i)); } template <class a, class b> stream& operator<<(pair <a,b> p) { return *this << "(" << p.first << ", " << p.second << ")"; } template <class c> stream& operator<<(rge<c> d) { *this << "["; for (auto it=d.b; it!=d.e; it++) *this << ", " + 2 * (it == d.b) << *it; return *this << "]"; } stream& _dbg(const string& s, int i, int b) { return *this; } template <class c, class ... cs> stream& _dbg(const string& s, int i, int b, c arg, cs ... args) { if (i == (int)(s.size())) return (*this << ": " << arg); b += (s[i] == '(') + (s[i] == '[') + (s[i] == '{') - (s[i] == ')') - (s[i] == ']') - (s[i] == '}'); return (s[i] == ',' && b == 0) ? (*this << ": " << arg << "     ")._dbg(s, i + 1, b, args...) : (s[i] == ' ' ? *this : *this << s[i])._dbg(s, i + 1, b, arg, args...); } };}
#define dout debug::stream()
#define dbg(...) ((dout << ">> ")._dbg(#__VA_ARGS__, 0, 0, __VA_ARGS__))
#define f first
#define s second
#define sc scanf
#define pr printf
#define mp make_pair
#define pb push_back
#define all(x) x.begin(),x.end()
#define ss(x) ((int)((x).size()))
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define per(i,a,b) for(int i=(b);i>=(a);i--)
#define upgrade cin.tie(0)->sync_with_stdio(0);
#define lowb(v,x) (lower_bound(all(v),(x))-v.begin())
#define uppb(v,x) (upper_bound(all(v),(x))-v.begin())
#define erase_duplicates(x) {sort(all(x));x.resize(unique(all(x))-x.begin());}
template <class p, class q> pair<p,q> operator-(pair<p,q> a, pair<p,q> b) { return mp(a.f - b.f, a.s - b.s); }
template <class p, class q> pair<p,q> operator+(pair<p,q> a, pair<p,q> b) { return mp(a.f + b.f, a.s + b.s); }
template <class p, class q> void umin(p &a, const q &b) { if (a > b) a = b; }
template <class p, class q> void umax(p &a, const q &b) { if (a < b) a = b; }
using lf=long double;
using ll=long long;
using cll=const ll;
using cint=const int;
using pll=pair<ll,ll>;
using pii=pair<int,int>;
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ //


const int N = 3005;
int n;
int t[N];
bool vis[N];
vector < vector <int> > answer;

void check()
{
	rep(i, 1, n) if (t[i] != i) return;
	printf("%d\n", ss(answer));
	for (auto& vec : answer){
		printf("%d\n", ss(vec));
		for (int a : vec){
			printf("%d ", a);
		}
		printf("\n");
	}
	exit(0);
}

void update()
{
	rep(i, 1, n) vis[i] = false;

	deque <int> query;
	
	rep(i, 1, n){
		if (vis[i] == true) continue;
		int u = i;
		deque <int> cycle;
		while (vis[u] == false){
			vis[u] = true;
			cycle.pb(u);
			u = t[u];
		}
		while (cycle.size() >= 2){
			int a = cycle.front();
			int b = cycle.back();
			query.push_front(a);
			query.push_back(b);
			cycle.pop_front();
			cycle.pop_back();
			swap(t[a], t[b]);
		}
	}

	answer.pb(vector <int>(all(query)));
}

int main()
{
	scanf("%d", &n);

	rep(i, 1, n) scanf("%d", &t[i]);

	vector < pair <int,int> > renum;

	rep(i, 1, n) renum.pb({t[i], i});

	sort(all(renum));

	int j = 1;

	for (auto p : renum) t[p.s] = j++;

	//rep(i, 1, n) dbg(i, t[i]);
	
	check();

	update();

	check();

	update();

	check();

	assert(false);

	return 0;
}