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#include <bits/stdc++.h>
using namespace std;
 
using ll = long long;
using db = double;
using ull = unsigned long long;
 
using pi = pair<int, int>;
using pl = pair<ll, ll>;
 
using vi = vector<int>;
using vl = vector<ll>;
using vpi = vector<pi>;
using vpl = vector<pl>;
 
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define f first
#define s second
 
#define tcT template<class T
#define tcTU tcT, class U
 
#define sz(x) int((x).size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define rep(i,a,b) for(int i = (a); i < (b); i++)
#define rrep(i,a,b) for(int i = (b) - 1; i >= (a); i--)
 
const db PI = acos(-1);
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count());
 
tcT> bool ckmin(T& a, const T& b) { return b < a ? a=b, 1 : 0; }
tcT> bool ckmax(T& a, const T& b) { return a < b ? a=b, 1 : 0; }
 
tcT> void _dbg(const char *sdbg, T h){ cerr<<sdbg<<'='<<h<<endl; }
tcT, class... TA> void _dbg(const char *sdbg, T h, TA... a) {
	while(*sdbg!=',') cerr<<*sdbg++;
	cerr<<'='<<h<<','; _dbg(sdbg+1, a...);
}
 
tcT> ostream &operator<<(ostream& os, vector<T> V) {
	os << "["; for (auto vv : V) os << vv << ","; return os << "]";
}
tcT, class V> ostream &operator<<(ostream &os, pair<T,V> P) {
	return os << "(" << P.f << "," << P.s << ")";
}
 
#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

const int MAXN = 3005;
int a[MAXN];
int n;
vector<vi> cycles;
bool vis[MAXN];

int mt[MAXN];

void scale() {
	map<int, int> sc;
	int sct = 0;
	rep(i,0,n) sc[a[i]];
	for (auto &[x, y] : sc) y=sct++;
	rep(i,0,n) a[i] = sc[a[i]];
}

int res = 1;

void gen_cycles() {
	cycles.clear();
	fill(vis, vis+n, false);
	rep(i,0,n) {
		if (vis[i]) continue;
		int cur = i;
		cycles.eb();
		do {
			vis[cur] = true;
			cycles.back().pb(cur);
			cur = a[cur];
		} while (cur != i);
		if (sz(cycles.back()) > 2) res = 2;
	}
}

void apply() {
	deque<int> ans;
	rep(i,0,n) {
		if (mt[i] == -1) continue;
		ans.push_front(i);
		ans.push_back(mt[i]);
		mt[mt[i]] = -1;
		mt[i] = -1;
	}
	assert(!ans.empty());
	for (int l = 0, r = sz(ans)-1; l < r; l++, r--) {
		swap(a[ans[l]], a[ans[r]]);
	}
	cout << sz(ans) << "\n";
	for (int x : ans) cout << x+1 << " ";
	cout << "\n";
}

void check_sorted() {
	rep(i,0,n) if (a[i] != i) return;
	cout << "0\n";
	exit(0);
}

signed main() {
	ios_base::sync_with_stdio(false); cin.tie(nullptr);

	cin >> n;
	rep(i,0,n) cin >> a[i];

	fill(mt, mt+n, -1);
	
	scale();
	check_sorted();

	gen_cycles();

	cout << res << "\n";
	if (res == 2) {
		for (auto &v : cycles) {
			if (sz(v) <= 2) continue;
			if (sz(v) % 2 == 1) {
				mt[v[0]] = v[1];
				mt[v[1]] = v[0];
				v.erase(v.begin());
			}
			int r = sz(v)-1;
			int l = 1;
			while (l < r) {
				mt[v[l]] = v[r];
				mt[v[r]] = v[l];
				l++;
				r--;
			}
		}
		apply();
		gen_cycles();
		fill(mt, mt+n, -1);
	}


	for (auto &v : cycles) {
		assert(sz(v) <= 2);
		if (sz(v) == 1) continue;
		if (sz(v) > 2) continue;
		mt[v[0]] = v[1];
		mt[v[1]] = v[0];
	}

	apply();

	rep(i,0,n) assert (a[i] == i);


	return 0;
}