---- +------------------+
/\ 18
18
\/
---- +------------------+-+-------------------+ 297
20
---- +----------------------------------------+
/\ 21 22 25
20
\/
---- +----------------------------------------+
/\ 23 24 26
27
40 ----+----------------------------------------+
/\ 28 30 29
16
\/ \/
---- ----L-----------------------------------------
/\
20
\/ \/
----L--------------------------------------------------------
210
<-------------------------------------------------->
.1.
4
20 10
<-----> <->
------------------------------------------------------------
/\ /\
3
\/
---- ---------------------------------------------
/\ /\ 01 02 03 16 19
17
\/
----+----------------------------------------+
/\ 08 09 10
20
73 04 05 06 07
\/
----+----------------------------------------+
/\ 11 12 15
10
\/
----+----------------------------------------+
13 14
\/
---- +----------------------------------------+
/\ 18 17
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