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#include<cstdio>
#include <iostream>
#include<string>
#include<algorithm>
#include <set>

using namespace std;
#define REP(x, n)  for(int x = 0; x < n; x++)
#define PB push_back
#define LL long long
#define MAX 1000005
#define FORD(x,b,e) for(int x = b; x >= e; x--)


// bool wayToSort(int i, int j) { return i > j; }






int main() {
	int n;
	int a[MAX];
	scanf("%d", &n);
	REP(x, n){
		scanf("%d", &(a[x]));
	}
	/*sort(a, a + n, wayToSort);
	REP(x, n){
		printf("%d\n", a[x]);
	}
	printf("\n");

	int * ones_it = std::find(a, a+n, 1);

	int ones = ones_it - a; // index pierwszej jedynki
	*/// printf("%d\n", ones);
	//int one_count =  n - ones; //ile jedynek
	// printf("%d %d\n", ones, one_count);
	int one_count =  std::count (a, a+n, 1);
	// printf("%d\n", one_count);


	if (one_count >= 2){
		printf("%d\n", 0);
		printf("%d\n", 2);
		printf("%d %d\n", 1, 2);
	}
	else{
		if (one_count == 1){
			printf("%d\n", 1);
			printf("%d\n", 2);
			printf("%d %d\n", 1, 2);	
		}	
		else{
			printf("%d\n", 2);
			printf("%d\n", 2);
			printf("%d %d\n", 1, 2);	
		}




	}

	// int arr_sum[MAX] = {};
/*	int arr_ref[MAX] = {};
		// printf("%d\n", arr_ref[4]);


	std::set<int>::iterator it;

  	std::set<int> myset;
  	if (a[0]<=one_count){
  		myset.insert(a[0]);
  		arr_ref[a[0]]=0;
  	}
  	for(int x = 1; x < ones; x++){
  		std::set<int> tempset;
  		if (a[x]<=one_count){
  			tempset.insert(a[x]);
  		  	arr_ref[a[x]] = 0;
		}
		// if (a[x]==2)
  			// break;
  		for (it=myset.begin(); it!=myset.end(); ++it){
  			    	// std::cout << ' ' << *it;
  			if (*it + a[x] - 2 <= one_count){
				tempset.insert(*it + a[x] - 2);
				arr_ref[*it + a[x] - 2]= a[x] - 2;
  			}
  		}
  		myset.insert(tempset.begin(), tempset.end());
  		printf("\n", a[x]);
  		for (it=myset.begin(); it!=myset.end(); ++it){
	 		printf("%d ", *it);
		}
		printf("\n", *it);

  	}

*/

/*
	LL wynik = 0;
	string word;
	// std::getline(std::cin, word);
	cin>>word;
	// scanf("%s", &word);
	// cout<<word<<endl;
	int ln = word.length();
	// cout<<ln<<endl;
	int start = 0;

	for(int x = 2; x < ln; x++){
		if (is_zero(word[x-2]) == is_zero(word[x-1]) &&  is_zero(word[x-1])== is_zero(word[x])){
			// cout<<word[x-2]<<word[x]<<word[x]<<endl;

			wynik += (x-start-1) * (ln - x);
			// cout<<x<< " "<<x-start-1<<" "<<ln-x<< " "<< wynik <<" " << x - 1<<endl;
			start = x - 1; 
		}
	}

	cout<<wynik<<endl;
*/

	return 0;
}