English

Reconstruction of complete interval tournaments. II

Combinatorics 2010-12-21 v1

Abstract

Let a, b (ba)a, \ b \ (b \geq a) and n (n2)n \ (n \geq 2) be nonnegative integers and let T(a,b,n)\mathcal{T}(a,b,n) be the set of such generalised tournaments, in which every pair of distinct players is connected at most with bb, and at least with aa arcs. In \cite{Ivanyi2009} we gave a necessary and sufficient condition to decide whether a given sequence of nonnegative integers D=(d1,d2,...,dn)D = (d_1, d_2,..., d_n) can be realized as the out-degree sequence of a TT(a,b,n)T \in \mathcal{T}(a,b,n). Extending the results of \cite{Ivanyi2009} we show that for any sequence of nonnegative integers DD there exist ff and gg such that some element TT(g,f,n)T \in \mathcal{T}(g,f,n) has DD as its out-degree sequence, and for any (a,b,n)(a,b,n)-tournament TT' with the same out-degree sequence DD hold aga\leq g and bfb\geq f. We propose a Θ(n)\Theta(n) algorithm to determine ff and gg and an O(dnn2)O(d_n n^2) algorithm to construct a corresponding tournament TT.

Keywords

Cite

@article{arxiv.1012.4210,
  title  = {Reconstruction of complete interval tournaments. II},
  author = {Antal Iványi},
  journal= {arXiv preprint arXiv:1012.4210},
  year   = {2010}
}