Minimizing picture words

  • Patrice Séébold
  • Karine Slowinski
Part III Communications
Part of the Lecture Notes in Computer Science book series (LNCS, volume 464)


With any word over the alphabet D = { r, r, u, ū }, we associate a connected picture in the following manner : the reading of each letter of this word induces a unit line : r ( r, u, ū resp.) stands for a right ( left, up, down resp.) move. We present a rewriting system which allows to obtain, from any word over D, all the words describing the same picture. Particularly, we give an algorithm to find in finite time, a minimal word describing a given picture : this word represents the shortest way to draw this picture "without pen-up".


Finite Time Unit Move Unit Line Formal Language Theory Basic Picture 
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-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • Patrice Séébold
    • 1
  • Karine Slowinski
    • 2
  1. 1.I.U.T. de Calais, dept. inform., C.N.R.S. - U.A. 369, L.I.F.L.Université de Lille1Villeneuve d'Ascq CédexFrance
  2. 2.C.N.R.S. - U.A. 369, L.I.F.L.Université de Lille1Villeneuve d'Ascq CédexFrance

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