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#include <cstdio>
using namespace std;
int n, a, oneCount;

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

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

    if (oneCount == 0) printf ("2\n");
    else if (oneCount == 1) printf ("1\n");
    else printf ("0\n");
    printf ("2\n");
    printf ("1 2\n");
}