a b c d e f   
f e d c b a   
b d a f b  e d b c e  b c a f f  c e a e f  b b e b e  
c e f e e  c d f f b  b a e f d  e e e c a  a e f a f  
a a e a e  f a e d f  b a c e e  a f e f d  f d e a b  
c a a e f  d f a c e  a e f a e  d f b a c  e e a f e 
ccafb aafcd bfbca ceddb aabda caada fcdcb afbac fcedc daedb 
dfced cfacc abdbb aebbf ccced bcdfb eadca cadbe dbbbe acada 
fecdd adefd fafaf eabfc bfacb edabe efbee acdbd cebfa defcd
fdedb eedfb feffc dceed dbeab cbdcf bffbb baede bbeeb acadd