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#include<bits/stdc++.h>
#include <unistd.h> 
#define st first
#define nd second
#define pb(x) push_back(x)
#define pp(x) pop_back(x)
#define mp(a, b) make_pair(a, b)
#define all(x) (x).begin(), (x).end()
#define rev(x) reverse(all(x))
#define sor(x) sort(all(x))
#define sz(x) (int)(x).size()
#define rsz(x) resize(x)

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii > vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef string str;
#define BOOST ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);  
mt19937 gen(getpid()); 
int n; 
const int MN = 3009; 
int tab[MN];  
int sorted[MN];   
int pier[MN];
int where[MN];  
map<int,int> conv; 
bool justgood =1; 
void prepare(){ 
	cin >> n; 
	for(int i = 1; i <= n; i++){ 
		cin >> tab[i];  
		sorted[i] = tab[i];  
	}
	sort(sorted + 1, sorted + n + 1);
	for(int i = 1; i <= n; i++) 
		conv[sorted[i]] = i; 
	for(int i = 1; i <= n ; i++)  
		pier[i] = conv[tab[i]];    
	for(int i = 1; i <= n; i++) 
		where[pier[i]] = i; 
	/*for(int i =1 ;i <=n ;i++) 
		cout << pier[i] << ' ' ; 
	cout << "\n"; */   
	for(int i = 1; i < n; i++){ 
		if(tab[i] > tab[i+1]) 
			justgood = 0; 
		}
	
}
bitset <MN> visited;  
pii put[MN];
  
bool checkifswapable(){ 
	bool good =1 ; 
	for(int i = 1; i <= n; i++){    
		if(pier[i] == i){ 
			continue; 
		} 
		if(pier[pier[i]] != i) 
			good = 0; 
	} 
	return good; 
}

void solve_swapable(){
	int ind = 0;  
	visited.reset();  
	for(int i = 1; i <= n; i++){ 
		if(pier[i] == i){
			visited[i] = 1; 
			continue; 
		} 
		else   {
			if(pier[pier[i]] == i && !visited[pier[i]] && !visited[i]){ 
				visited[i] = 1; 
				visited[pier[i]] = 1; 
				put[ind++] = {i, pier[i]}; 
			}  
		} 
	} 
	cout << 2 * ind << "\n"; 
	for(int i = 0; i < ind; i++) 
		cout << put[i].st << ' '; 
	for(int i = ind -1; i > -1; i--) 
		cout << put[i].nd << ' '; 			
} 

void repair(){ 
	int ind = 0; visited.reset(); 
	int todo = n; 
	for(int i = 1; i <= n; i++){ 
		if(pier[i] == i){ 
			todo--; 
			visited[i] = 1;  
			continue; 
		}  
		if(pier[pier[i]] == i && !visited[pier[i]] && !visited[i]){ 
			todo -= 2; 
			visited[pier[i]] =1 ; 
			visited[i] = 1; 
		}
	}   
	int preffree = 1; 
	int pocz = -1, value; 
	for(int i = 1; i <=n; i++){ 
		if(!visited[i]){ 
			pocz = i;  
			value = pier[i]; 
			break; 
		}  
	}   
	int doppoz, buf;  
	//for(int i  =1; i <=n ;i++) 
		//cout << visited[i] << ' ';   
	//cout << "\n";  
	bool done;  int rund = 0;  
	int zost = n - visited.count(); 
	while( preffree < n){
		//cout << "START: " << pocz << ' '  << value << "\n";  
		visited[pocz] = 1;  
		doppoz = where[pocz];   
		rund++;    
		zost--;  
		done = 0; 
		if(value != pocz){ // nie zamieniamy dobrego jedynaka
			if(pier[value] != pocz && !visited[value] && !visited[where[pocz]]){ //gdy dobra para od razu
			put[ind++] = {where[pocz], value};   
			zost--; 
			//cout <<"\nrow " << where[pocz] << ' ' << value  << "\n";  
			visited[value] =1;  
			visited[where[pocz]] = 1;  
			todo -= 1;   
			if(pier[value] != where[pocz] ){ 
				buf = pocz; 
				pocz = where[buf]; 
				//cout << "WARFIN " << value << ' ' << pier[value] << "\n";  
				value  = pier[value];  
				done =1 ; 
			}   
		} 
	} 
	if(!done){ 
		for(int i = preffree; i <= n; i++){ 
			if(visited[i]) 
				preffree++; 
			else{
				pocz = i;
				value = pier[i];  
				break; 
				} 
			} 
			preffree++; 
		} 
	} 
	cout <<  2 * ind << "\n"; 
	for(int i = 0; i < 	 ind; i++) 
		cout <<  put[i].st << ' '; 
	for(int i = ind -1 ;  i > - 1; i--) 
		cout << put[i].nd << ' '; 
	for(int i =0; i < ind; i++){ 
		swap(pier[put[i].st], pier[put[i].nd]); 
	}
	// tutaj musi byc najmadrzejsza petla na swiecie , ktora jest efektywnie rozwiazaniem calego zadania
	
}
	
void run(){ 
	if(justgood){ 
		cout << 0; 
		return; 
	}
	if(!checkifswapable()){ 
		cout << 2 << "\n"; 
		repair();  
		cout << "\n"; 
		solve_swapable();  
	} 
	else { 
		cout << 1 << "\n"; 
		solve_swapable(); 
	}
	
}
int main(){ 
	prepare(); 
	run() ; 
}