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#include <cstdio>

int main() {
    int n;
    scanf("%d",&n);
    int ones=0;
    for(int i=0;i<n;i++) {
        int a_i;
        scanf("%d", &a_i);
        if(a_i == 1)
            ones+=1;
    }
    
    if(ones == 0)
            printf("2\n2\n1 2\n");
    else if(ones == 1)
            printf("1\n2\n1 2\n");
    else
        printf("0\n2\n1 2\n");
    
    return 0;
}