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#include <cstdio>
#include <iostream>

using namespace std;

int main()
{
    int n,a,m=0;
    scanf("%d",&n);
    for(int i=0; i<n; i++)
    {
        scanf("%d",&a);
        if(a==1) m++;
    }
    if(m>1) cout<<0<<endl<<2<<endl<<1<<" "<<2;
    else if(m==1) cout<<1<<endl<<2<<endl<<1<<" "<<2;
    else cout<<2<<endl<<2<<endl<<1<<" "<<2;
    return 0;
}