Rough Dentogram ( clustering based on segment distance )

    E 30  32  
   !  
   5-- E 23  25  
   !     
   4----- L 26  29  
   !        
   !         L 20  22  
   !        !  
   3--------2-- L 11  19  
   !              
   1-------------- L  1  10  
   !                 
   6----------------- L 33  41  
   !                    
   7-------------------- L 42  50  
  /
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