879199 sk: 613d 75
Zeroes are dots here.
See there are 5 all-zero
and 7 non-zero groups.
16 groups are all together.
The rest is easy. There are
exactly 16-7-5=4 mixed.
Those mixed you shall
see easily:
.... .... .... ....
.... 55f7 aa67 6341
c..9 a7fe 5bf. .6db
7648 3eed e7.b 613d