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#pragma GCC optimize ("Ofast")
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define FOR(i, a, b) for (auto i=(a); i<(b); i++)
#define FORD(i, a, b) for (int i=(a); i>(b); i--)
#define SZ(x) ((int)(x).size())
#define ALL(x) (x).begin(), (x).end()
#define PPC(x) __builtin_popcountll(x)
#define MSB(x) (63 - __builtin_clzll(x))
#define LSB(x) __builtin_ctzll(x)
#define ARG(x, i) (get<i>(x))
#define ithBit(m, i) ((m) >> (i) & 1)
#define pb push_back
#define ft first
#define sd second
#define kw(a) ((a) * (a))
#ifdef DEBUG
#include "debug.h"
#else
#define dbg(...) 0
#endif
using namespace std; 

template <typename T1, typename T2> inline void remin(T1& a, T2 b) { a = min(a, (T1)b);	}
template <typename T1, typename T2> inline void remax(T1& a, T2 b) { a = max(a, (T1)b);	}

const int maxN = 1 << 12, INF = 1 << 30;

int n, T[maxN];

void intoPerm()
{
	map <int, int> M;
	FOR(i, 1, n+1)
		M[T[i]] = 1;
	int ctr = 1;
	for (auto& [k, v] : M)
		v = ctr++;
	FOR(i, 1, n+1)
		T[i] = M[T[i]];
}
	
auto getCycles()
{
	vector <list <int> > C(0);
	vector <bool> vis(n+1, false);
	FOR(i, 1, n+1) if (!vis[i])
	{
		list <int> c(0);
		for (int v = i; !vis[v]; v = T[v])
			c.pb(v), vis[v] = true;
		C.pb(c);	
	}
	return C;
}

void procCycle(list <int>& c, vector <vector <pair <int, int> > >& res)
{
	FOR(d, 0, 2)
	{
		if (SZ(c) < 2)
			break;
			
		auto it = c.begin(), jt = prev(c.end());
		FOR(_, 0, SZ(c) / 2)
			res[d].pb({*it++, *jt--});
			
		c.erase(c.begin());
	}
}

void print(vector <pair <int, int> >& P)
{
	printf("%d\n", SZ(P) * 2);
	for (auto [a, _] : P)
		printf("%d ", a);
	reverse(ALL(P));
	for (auto [_, b] : P)
		printf("%d ", b);
	printf("\n");	
}

void solve()
{
	scanf ("%d", &n);
	FOR(i, 1, n+1)
		scanf ("%d", T+i);
	intoPerm();
	auto C = getCycles();
	vector <vector <pair <int, int> > > res(2, vector <pair <int, int> > {});
	for (auto& c : C)
		procCycle(c, res);
	while (!res.empty() and res.back().empty())
		res.pop_back();
	printf("%d\n", SZ(res));
	for (auto& P : res)
		print(P);	
}
 
int main()
{
	int t = 1;
	//scanf ("%d", &t);
	FOR(tid, 1, t+1)
	{
		//printf("Case #%d: ", tid);
		solve();
	}
	return 0;
}