I am looking at some k-maps and puzzled about grouping the adjacent cells. Pretend this is a 4 variable k-map of F(A,B,C,D) (sorry, I don't know of a better way to display them):

1100

1001

1001

1100

I see 3 groups:

1100

1001

1001

1100

1100

1001

1001

1100

1100

1001

1001

1100

Are these 3 groups correct?

Also, pretend this is another 4 variable k-map:

0111

0111

0111

0111

How do you group these? It looks like one big group, but the size can't be 12 so I am stumped... Is it 3 groups, each containing the entire column?