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#include <cstdio>
#include <algorithm>

int main() {
    int n, tmp;
    scanf("%d", &n);
    int ones = 0;
    for(int i = 0; i < n; ++i)
        scanf("%d", &tmp), ones += (tmp == 1);
    printf("%d\n", std::max(2-ones, 0));
    printf("2\n");
    printf("1 2\n");
    return 0;
}