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#include <iostream>
#include <cstdio>

using namespace std;

int n;
int il_1;
int a;

int main()
{
    scanf( "%d", &n );
    for( int i=0; i<n; i++ )
    {
        scanf("%d",&a);
        if( a == 1 )
        {
            il_1++;
        }
    }
    if( il_1 == 0 ) printf("2\n");
    else if( il_1 == 1 ) printf("1\n");
    else printf("0\n");
    printf("2\n1 2\n");
    return 0;
}