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#include <bits/stdc++.h>
using namespace std;
using LL = long long;
#define e1 first
#define e2 second
#define pb push_back
#define OUT(x) {cout << x << "\n"; exit(0); }
#define TCOUT(x) {cout << x << "\n"; return; }
#define FOR(i, l, r) for(int i = (l); i <= (r); ++i)
#define rep(i, l, r) for(int i = (l); i < (r); ++i)
#define boost {ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); }
#define sz(x) int(x.size())
#define trav(a, x) for(auto& a : x)
#define all(x) begin(x), end(x)
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
#ifdef DEBUG
template<class T> int size(T &&x) {
	return int(x.size());
}
template<class A, class B> ostream& operator<<(ostream &out, const pair<A, B> &p) {
	return out << '(' << p.first << ", " << p.second << ')';
}
template<class T> auto operator<<(ostream &out, T &&x) -> decltype(x.begin(), out) {
	out << '{';
	for(auto it = x.begin(); it != x.end(); ++it)
		out << *it << (it == prev(x.end()) ? "" : ", ");
	return out << '}';
}
void dump() {}
template<class T, class... Args> void dump(T &&x, Args... args) {
	cerr << x << ";  ";
	dump(args...);
}
#endif
#ifdef DEBUG
  struct Nl{~Nl(){cerr << '\n';}};
# define debug(x...) cerr << (strcmp(#x, "") ? #x ":  " : ""), dump(x), Nl(), cerr << ""
#else
# define debug(...) 0 && cerr
#endif
typedef vector<pii> vpi;
vi skal(vi vec) {
	int n = sz(vec);
	vpi skal(n);
	vi ret(n);
	rep(i, 0, n) skal[i] = {vec[i], i};
	sort(all(skal));
	rep(i, 0, n) ret[skal[i].e2] = i;
	return ret;
}

int main() {
	boost;
	int n;
	cin >> n;
	vi vec(n);
	rep(i, 0, n) cin >> vec[i];
	vec = skal(vec);
	debug(vec);
	vector <vpi> odp;
	int tryhard = 0;
	while (true) {
		debug(vec);
		bool ok = true;
		rep(i, 0, n) if (vec[i] != i) ok = false;
		if (ok) {
			assert(sz(odp) <= 2);
			cout << sz(odp) << "\n";
			trav(ciag, odp) {
				cout << 2 * sz(ciag) << "\n";
				for (auto [a, b] : ciag) cout << a + 1 << ' ';
				for (int i = sz(ciag) - 1; i >= 0; --i) cout << ciag[i].second + 1 << ' ';
				cout << "\n";
			}
			exit(0);
		}
		
		vector <bool> odw(n, false);	
		vpi swaps;
		rep(i, 0, n) {
			if (vec[i] == i || odw[i]) continue;
			vi vis;
			int j = i;
			while (!odw[j]) {
				odw[j] = true;
				vis.pb(j);
				j = vec[j];
			}
			
			if (tryhard == 0 && sz(vis) != 2) { //magically swap the cycle differently
				int viss = sz(vis);
				for (int iter = 1; iter < viss - iter; ++iter) {
					int a = vis[iter], b = vis[viss - iter];
					swaps.push_back({a, b});
				}
				
			}
			else {
				assert(sz(vis) == 2);
				for (int iter = 1; iter < sz(vis); iter += 2) {
					int a = vis[iter - 1], b = vis[iter];
					swaps.push_back({a, b});
				}
			}
		}
		tryhard += 1;
		
		trav(zam, swaps) swap(vec[zam.e1], vec[zam.e2]);
		odp.push_back(swaps);
	}
}