The problem of computing the rooted subtree prune and regraft (rSPR) distance of two phylogenetic trees is computationally hard and so is the problem of computing the hybridization number of two phylogenetic trees (denoted by Hybridization Number Computation [HNC]). Since they are important problems in phylogenetics, they have been studied extensively in the literature. Indeed, quite a number of exact or approximation algorithms have been designed and implemented for them. In this article, we design and implement several approximation algorithms for them and one exact algorithm for HNC. Our experimental results show that the resulting exact program is much faster (namely, more than 80 times faster for the easiest dataset used in the experiments) than the previous best and its superiority in speed becomes even more significant for more difficult instances. Moreover, the resulting approximation program's output has much better results than the previous bests; indeed, the outputs are always nearly optimal and often optimal. Of particular interest is the usage of the Monte Carlo tree search (MCTS) method in the design of our approximation algorithms. Our experimental results show that with MCTS, we can often solve HNC exactly within short time.

中文翻译：

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有根子树修剪和再移植 (rSPR) 距离和杂交数的改进实用算法。

计算两棵系统发育树的有根子树修剪和再移植 (rSPR) 距离的问题在计算上很困难，计算两棵系统发育树的杂交数（由杂交数计算 [HNC] 表示）的问题也是如此。由于它们是系统发育学中的重要问题，因此在文献中对其进行了广泛的研究。事实上，已经为它们设计和实现了相当多的精确或近似算法。在本文中，我们为它们设计并实现了几种近似算法，并为 HNC 设计并实现了一种精确算法。我们的实验结果表明，生成的精确程序要快得多（即，实验中使用的最简单数据集比之前最好的数据集快 80 倍以上，并且对于更困难的实例，其速度优势变得更加显着。此外，由此产生的近似程序的输出结果比以前的最佳结果要好得多；事实上，输出总是接近最优，而且常常是最优的。特别令人感兴趣的是蒙特卡罗树搜索 (MCTS) 方法在我们的近似算法设计中的使用。我们的实验结果表明，使用 MCTS，我们通常可以在短时间内准确地解决 HNC。特别令人感兴趣的是蒙特卡罗树搜索 (MCTS) 方法在我们的近似算法设计中的使用。我们的实验结果表明，使用 MCTS，我们通常可以在短时间内准确地解决 HNC。特别令人感兴趣的是蒙特卡罗树搜索 (MCTS) 方法在我们的近似算法设计中的使用。我们的实验结果表明，使用 MCTS，我们通常可以在短时间内准确地解决 HNC。