Finding a majority ball with majority answers

نویسندگان

  • Máté Vizer
  • Dániel Gerbner
  • Balázs Keszegh
  • Dömötör Pálvölgyi
  • Balázs Patkós
  • Gábor Wiener
چکیده

Suppose we are given a set of n balls {b1, . . . , bn} each colored either red or blue in some way unknown to us. To find out some information about the colors, we can query any triple of balls {bi1 , bi2 , bi3}. As an answer to such a query we obtain (the index of) a majority ball, that is, a ball whose color is the same as the color of another ball from the triple. Our goal is to find a non-minority ball, that is, a ball whose color occurs at least n2 times among the n balls. We show that the minimum number of queries needed to solve this problem is Θ(n) in the adaptive case and Θ(n3) in the non-adaptive case.

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عنوان ژورنال:
  • Electronic Notes in Discrete Mathematics

دوره 49  شماره 

صفحات  -

تاریخ انتشار 2015