Consider a digraph where the vertices represent people and an arc (i,j) represents the possibility of i giving a gift to j. The basic question we pose is whether there is an anonymity-preserving “gift assignment” such that each person makes and receives exactly one gift, and such that no person i can infer the remaining gift assignments from the fact that i is assigned to give a gift to j. We formalize this problem as a graph property involving vertex disjoint circuit covers, give a polynomial algorithm to decide this property for any given graph and provide a computational validation of the algorithm.


Acceptable Solution Polynomial Algorithm ILOG CPLEX Connected Digraph Bipartite Digraph 
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 2008

Authors and Affiliations

  • Leo Liberti
    • 1
  • Franco Raimondi
    • 2
  1. 1.LIXÉcole PolytechniquePalaiseauFrance
  2. 2.Dept. of Computer ScienceUniversity College LondonUK

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