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#include <iostream>

using namespace std;

int main() {
int count;
cin>>count;
int ones = 0;
for(int i=0;i<count;i++) {
int b;
cin>>b;
if (b == 1) ones++;
}
cout<<(ones > 2 ? 0 : (2 - ones)) << endl;
cout<<2<<endl;
cout<<"1 2"<<endl;
return 0;
}