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#include <bits/stdc++.h>
using namespace std;
//{
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define VAR(v, i) __typeof(i) v=(i)
#define all(v) (v).begin(),(v).end()
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)


#define PII pair<int,int>
#define st first
#define nd second
#define pb push_back
#define lint long long int
#define VI vector<int>

#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
	*this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
};
//{
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

#define make( x) int (x); scanf("%d",&(x));
#define make2( x, y) int (x), (y); scanf("%d%d",&(x),&(y));
#define make3(x, y, z) int (x), (y), (z); scanf("%d%d%d",&(x),&(y),&(z));
#define make4(x, y, z, t) int (x), (y), (z), (t); scanf("%d%d%d%d",&(x),&(y),&(z),&(t));
#define makev(v,n) VI (v); FOR(i,0,(n)) { make(a); (v).pb(a);} 
#define IOS ios_base::sync_with_stdio(0)
#define HEAP priority_queue

#define read( x) scanf("%d",&(x));
#define read2( x, y) scanf("%d%d",&(x),&(y));
#define read3(x, y, z) scanf("%d%d%d",&(x),&(y),&(z));
#define read4(x, y, z, t) scanf("%d%d%d%d",&(x),&(y),&(z),&(t));
#define readv(v,n) FOR(i,0,(n)) { make(a); (v).pb(a);}
#define jeb() fflush(stdout);
//}

int name[3005];
bool na_cyklu[3005];
vector<VI> cykle;

int main() {
	make(n);
	VI v; v.pb(0);
	readv(v, n);

	VI sorted = v;
	sort(all(sorted));
	
	FOR(i,0,n+1) {
		name[sorted[i]] = i;
	}
	FOR(i,0,n+1) {
		v[i] = name[v[i]];
	}
	
	int max_cyc = 0;

	FOR(i,0,n+1) na_cyklu[i] = false;
	FOR(i,0,n+1) {
		if (na_cyklu[i]) continue;
		VI cykl; cykl.pb(i);
		na_cyklu[i] = true;
		while (v[cykl.back()] != i) {
			na_cyklu[v[cykl.back()]] = true;
			cykl.pb(v[cykl.back()]);
		}
		cykle.pb(cykl);
		max_cyc = max(max_cyc, (int) cykl.size());
	}
	/*cout << max_cyc << endl;
	debug() << imie(cykle);
	*/

	if (max_cyc == 1) {
		printf("0\n");
		return 0;
	}
	if (max_cyc == 2) {
		printf("1\n");
		VI ans1;
		VI ans2;
		int k = 0;
		FOR(i,0,cykle.size()) {
			if (cykle[i].size() == 2) {
				ans1.pb(cykle[i][0]);
				ans2.pb(cykle[i][1]);
				k++;
			}
		}
		printf("%d\n", 2*k);
		FOR(i,0,k) printf("%d ", ans1[i]);
		FOR(i,0,k) printf("%d ", ans2[k-1-i]);
		printf("\n");
		return 0;
	} 
	printf("2\n");
	VI ans1, ans2, ans3, ans4;
	FOR(i,0,cykle.size()) {
		if (cykle[i].size() == 2) {
			ans1.pb(cykle[i][0]);
			ans2.pb(cykle[i][1]);
		}
		if (cykle[i].size() >= 3) {
			int l = cykle[i].size();
			if (l % 2 == 0) {
				int x = 0, y = l-3;
				while (x < y) {
					ans1.pb(cykle[i][x]); ans2.pb(cykle[i][y]); ans3.pb(cykle[i][x]); ans4.pb(cykle[i][y+1]);
					x++; y--;
				}
				ans1.pb(cykle[i][l-2]); ans2.pb(cykle[i][l-1]);
			} else { 
				int x = 0, y = l-2;
				while (x < y) {
					ans1.pb(cykle[i][x]); ans2.pb(cykle[i][y]); ans3.pb(cykle[i][x]); ans4.pb(cykle[i][y+1]);
					x++; y--;
				}
			}
		}
	}
	int k1 = ans1.size();
	printf("%d\n", 2*k1);
	FOR(i,0,k1) printf("%d ", ans1[i]);
	FOR(i,0,k1) printf("%d ", ans2[k1-1-i]);
	printf("\n");
	int k2 = ans3.size();
	printf("%d\n", 2*k2);
	FOR(i,0,k2) printf("%d ", ans3[i]);
	FOR(i,0,k2) printf("%d ", ans4[k2-1-i]);
	printf("\n");


}