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#include <bits/stdc++.h>
using namespace std;

const int N = 3000 + 9;
int n;
int v[N];

void rescale() {
	int used[N];
	for (int i=0; i<N; ++i) used[i] = -2;
	for (int i=0; i<n; ++i) used[v[i]] = -1;
	int next = -1;
	for (int i=0; i<N; ++i) if (used[i] == -1) used[i] = ++next;
	for (int i=0; i<n; ++i) v[i] = used[v[i]];
}

void fillStep(deque<int> &q) {
	int done[N];
	for (int i=0; i<n; ++i) done[i] = 0;

	for (int i=0; i<n; ++i) if (0 == done[i]) {
		vector<int> cycle;
		int start = i;
		cycle.push_back(i);
		done[i] = 1;
		for (int j=v[i]; j!=start; j=v[j]) {
			done[j] = 1;
			cycle.push_back(j);
		}
		int a = 0;
		int b = cycle.size() - 1;
		while (a < b) {
			q.push_front(cycle[a]);
			q.push_back(cycle[b]);
			swap(v[cycle[a]], v[cycle[b]]);
			++a;
			--b;
		}
	}
}

void printStep(deque<int> &q) {
	if (q.empty()) return;
	printf("%d\n", (int)q.size());
	for (int i=0; i<q.size(); ++i)
		printf("%d%s", q[i] + 1, i+1<q.size() ? " " : "\n");
}

void solve() {
	deque<int> step1;
	fillStep(step1);
	deque<int> step2;
	fillStep(step2);

	int cnt = 0;
	if (!step1.empty()) ++cnt;
	if (!step2.empty()) ++cnt;

	printf("%d\n", cnt);
	printStep(step1);
	printStep(step2);
}

int main() {
	scanf("%d", &n);
	for (int i=0; i<n; ++i) scanf("%d", v + i);
	rescale();
	solve();

	return 0;
}