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

#define st first
#define nd second
#define mp make_pair
#define pb push_back
#define all(x) x.begin(), x.end()
#define boost ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)

typedef long long lli;
typedef pair<int, int> pii;
typedef pair<lli, lli> pll;
typedef pair<lli, int> pli;
typedef pair<int, lli> pil;

int n, a, jed=0;

int main()
{
    boost;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        cin>>a;
        if(a==1)jed++;
    }
    int x=2-min(jed, 2);
    cout<<x<<"\n";
    cout<<2<<"\n";
    cout<<1<<' '<<2<<"\n";
	return 0;
}