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#include <bits/stdc++.h>
using namespace std;
const int N = 3007;
int A[N],P[N],vis[N],B[N];
void swp(int a,int b){
	P[A[a]] = b;
	P[A[b]] = a;
	swap(A[a],A[b]);
}
void solve(){
	int n;
	cin>>n;
	set<int> S;
	for(int i = 1;i<=n;i+=1){
		cin>>A[i];
//		A[i] = i;
		S.insert(A[i]);
		vis[i] = 0;
	}
//	random_shuffle(A+1,A+1+n);
	int ptr = 0;
	map<int,int> M;
	for(int to:S){
		M[to] = ++ptr;
	}
	/*for(int i = 1;i<=n;i+=1){
		A[i] = i;
	}
	random_shuffle(A+1,A+1+n);*/
	for(int i = 1;i<=n;i+=1){
		A[i] = M[A[i]];
		P[A[i]] = i;
		B[i] = A[i];
//		cout<<A[i]<<' ';
	}
//	cout<<endl;
	vector<vector<pair<int,int> > > ans;
	int flag = 0;
	for(int i = 1;i<n;i+=1){
		if (A[i]>A[i+1]){
			flag = 1;
			break;
		}
	}
	if (flag){
		flag = 0;
		for(int i = 1;i<=n;i+=1){
			if (P[P[i]]!=i){
				flag = 1;
				break;
			}
		}
		if (flag){
			ans.resize(2);
			for(int i = 1;i<=n;i+=1){
				if (!vis[i]){
					vector<int> seq;
					int x = i;
					do{
						vis[x] = 1;
						seq.push_back(x);
						x = A[x];
					}while(x!=i);
					int sz = seq.size();
//					cout<<"GDB "<<sz<<endl;
//					for(int to:seq){
//						cout<<to<<' ';
//					}
//					cout<<endl;
					for(int i = 1;i<sz-i;i+=1){
						ans[0].push_back({P[seq[i]],P[seq[sz-i]]});
						swp(P[seq[i]],P[seq[sz-i]]);
					}
				}
			}
		}
		else{
			ans.resize(1);
		}
		for(int i = 1;i<=n;i+=1){
			if (A[i]!=i){
				int pos = P[i];
				ans.back().push_back({i,pos});
				swp(i,pos);
			}
		}
	}
	for(int i = 1;i<n;i+=1){
		if (A[i]>A[i+1]){
			assert(0);
		}
	}
	if (ans.size()>2){
		for(int i = 1;i<=n;i+=1){
			cout<<B[i]<<' ';
		}
		cout<<endl;
		exit(0);
	}
	else{
	}
	cout<<ans.size()<<endl;
	for(auto &V:ans){
		int sz = V.size();
		cout<<sz*2<<endl;
		for(int c = 0;c<2;c+=1){
			for(auto &to:V){
				cout<<to.first<<' ';
				swap(to.first,to.second);
			}
			reverse(V.begin(),V.end());
		}
		cout<<endl;
	}
}
signed main(){
	int tt = 1;
	while(tt--){
		solve();
	}
}