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#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(int i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...)<<'\n';}(x)
#else
#define debug(...) {}
#endif

int main() {
	cin.tie(0)->sync_with_stdio(0);
	int n;
	cin >> n;
	vector t(n, 0);
	vector<pair<int, int>> sr;
	REP (i, n) {
		cin >> t[i];
		sr.emplace_back(t[i], i);
	}
	sort(sr.begin(), sr.end());
	vector ind(n, 0);
	REP (i, n)
		ind[sr[i].second] = i;
	debug(ind);

	vector<vector<int>> lf(2), rg(2);
	vector odw(n, 0);
	REP (i, n) {
		if (odw[i])
			continue;
		int x = i;
		vector<int> cur;
		while (!odw[x]) {
			odw[x] = 1;
			cur.emplace_back(x);
			x = ind[x];
		}
		if (ssize(cur) == 1)
			continue;
		REP (j, ssize(cur) / 2) {
			lf[0].emplace_back(cur[j]);
			rg[0].emplace_back(cur[ssize(cur) - 1 - j]);
		}
		if (ssize(cur) == 2)
			continue;
		cur.erase(cur.begin());
		REP (j, ssize(cur) / 2) {
			lf[1].emplace_back(cur[j]);
			rg[1].emplace_back(cur[ssize(cur) - 1 - j]);
		}
	}

	debug(lf);
	debug(rg);
	REP (i, 2)
		lf[i].insert(lf[i].end(), rg[i].rbegin(), rg[i].rend());

	while (ssize(lf) && ssize(lf.back()) == 0)
		lf.pop_back();

	cout << ssize(lf) << '\n';
	for (auto v : lf) {
		cout << ssize(v) << '\n';
		for (int i : v)
			cout << i + 1 << ' ';
		cout << '\n';
	}
}