% ruby space.rb display public1.in 
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Earth         Kirk 
Vulcan        
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Enterprise docking at Earth
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Earth         Kirk 
  Enterprise   
Vulcan        
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Kirk boarding Enterprise at Earth
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Earth         
  Enterprise   Kirk 
Vulcan        
----------------------------------------
Enterprise departing from Earth
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Earth         
Vulcan        
----------------------------------------
Enterprise docking at Vulcan
----------------------------------------
Earth         
Vulcan        
  Enterprise   Kirk 
----------------------------------------
Kirk departing Enterprise at Vulcan
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Earth         
Vulcan        Kirk 
  Enterprise   
----------------------------------------