---| 14 |-----------------------------------------

40    -------------------------------------------------------------------------|
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30    -                 O                                    O                 |
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      |        \                                                      /        |
      |             \                                            /             |
20    -                 \        _         _        _        /                 |
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10    -                                                                        |
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0     ------------------|------------------|-----------------|-----------------|
     20                30                 40                50                60
                                the smiley face graph