在圖論(graph)的領域中,競賽圖(tournament)是一個相當有趣的研究。Brualdi and Li有一篇論文是探討相同分數序列競賽圖的特性,並推導出了競賽圖的最小分數序列(minimum score sequence),及其中3迴圈(3-cycles)的個數為n – 2個。 本篇論文探討最小競賽圖(minimum tournament)與生成樹(spanning trees)間的關係。我們提出一個找尋最小競賽圖中所有的3迴圈的演算法,並且證明其所需要的時間複雜度為O(m + n),其中n是點的個數,m是所有點的外分支度(out-degree)的總和。 在圖論(graph)的領域中,競賽圖(tournament)是一個相當有趣的研究。Brualdi and Li有一篇論文是探討相同分數序列競賽圖的特性,並推導出了競賽圖的最小分數序列(minimum score sequence),及其中3迴圈(3-cycles)的個數為n – 2個。 本篇論文探討最小競賽圖(minimum tournament)與生成樹(spanning trees)間的關係。我們提出一個找尋最小競賽圖中所有的3迴圈的演算法,並且證明其所需要的時間複雜度為O(m + n),其中n是點的個數,m是所有點的外分支度(out-degree)的總和。
Tournaments have many interesting research topic in the field of graph theory. Brualdi and Li have proved that the number of 3-cycles of minimum tournaments formed by the minimum score sequence is n – 3。 In this thesis, we discuss the relation between a minimum tournament and its spanning tree. We propose an algorithm for finding all 3-cycles of minimum tournaments and prove that its time complexity is O(m + n), where n is the number of nodes and m is the total number of out-degrees in the tournaments.