NN NNNNNNNNNNNN
NNNNNNNNNNNNN NNNNNNNNNNN NNNNNN N NN N NNNNN
NNN NN NN NN NN NN NN NNN
NN NNN NN N NN NN NN NNNNNN
NN NNN NNNNNNN NNNNNNNNNNNN NN NNNNNN
NNN NN NN N NNN NNN NN NNN
NNNNNNNNNNNNN NN NN NNN NNNNNNN NNN
NNNNNNNNNN NNNN NNNNNNN NNNNN