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#include<bits/stdc++.h>
using namespace std;

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	
	int n,a,xd=0;
	cin>>n;
	for(int i=1; i<=n; i++){
		cin>>a;
		if(a==1) xd++;
	}
	
	if(!xd) cout<<"2\n";
	else if(xd==1) cout<<"1\n";
	else cout<<"0\n";
	
	cout<<"2\n";
	cout<<"1 2\n";
	return 0;
}