A B C D E F G H I J K L M N O
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  1 └┴┴┴┴┴┴┴┴┴┴┴┴┴┘ 

[ 1]● ==> H8	[ 2]○ ==> I9	[ 3]● ==> H6	[ 4]○ ==> G9	[ 5]● ==> J8
[ 6]○ ==> I7	[ 7]● ==> J6	[ 8]○ ==> G7	[ 9]● ==> J7	[10]○ ==> J9
[11]● ==> H9	[12]○ ==> H7	[13]● ==> I6	[14]○ ==> K6	[15]● ==> H5
[16]○ ==> K8	[17]● ==> G5	[18]○ ==> I5	[19]● ==> G4	[20]○ ==> F3
[21]● ==> H4	[22]○ ==> F7	[23]● ==> E7	[24]○ ==> F4	[25]● ==> E6