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

int main ()
{
    int n;
    scanf("%d", &n);    

    int cnt = 0;

    for (int i = 0; i < n; ++i)
    {
        int a;
        scanf("%d", &a);
        if (a == 1)  
            ++cnt;
    }

    printf("%d\n", 2 - min(cnt, 2));
    printf("2\n1 2\n");

    return 0;
}