symetry

rot180 , 180 degrees rotational symmetry.
 pub -> bnp

reflect 180 vertical
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madamiamadam
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 reflect 180 horizontal
  ----HOE-----

 no rotational or reflectional symmetry
 Quip
 infinite degrees of reflectional and rotational symmetry
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 ---O---
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 180 deg rotational symmetry, and horizontal and vertical reflectional symmetry
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 ---I--
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 180 deg identity rotational symmetry
    SOS  -> SOS
vertical reflectional symmetry
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    !
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