Rough Dentogram ( clustering based on segment distance )

    L 23  26  
   !  
   5-- L 11  14  
   !     
   !      E 37  38  
   !     !  
   !     8-- E 27  28  
   !     !     
   !     !      E 21  22  
   !     !     !  
   !     !     4-- E 15  16  
   !     !     !     
   6-----2-----3----- L 17  20  
   !                    
   1-------------------- L  1  10  
   !                       
   7----------------------- L 29  36  
  /
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