Functional Pearl: Nearest Shelters in Manhattan

  • Shin-Cheng Mu
  • Ting-Wei Chen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8858)


Godzilla is attacking New York, and your task is to choose, for each shelter in the city, a nearest shelter to evacuate to. Luckily, distance between shelters is measured by Manhattan length, which allows us to complete the task in O(n logn) time. We present two algorithms: an algorithmic solution that solves the problem by a list-homomorphism, and a data structure based solution that exploits a “thinning” property.


Recursive Call Proof Obligation Manhattan Distance Binary Search Tree Input List 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Shin-Cheng Mu
    • 1
  • Ting-Wei Chen
    • 2
  1. 1.Institute of Information ScienceAcademia SinicaTaipeiTaiwan
  2. 2.Dep. of Computer Science and Information EngineeringNational Taiwan UniversityTaipeiTaiwan

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