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arXiv 1412.2437cs.DScs.DM
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求解时间复杂度为时间复杂度区间(O(n^4),O(n^3 * 2^n))的旅行商问题的一个新的精确算法

A New Exact Algorithm for Traveling Salesman Problem with Time Complexity Interval (O(n^4), O(n^3*2^n))

Yunpeng Li

摘要:

旅行商问题是一个NP难问题。到目前为止,研究人员还没有找到一个多项式时间算法来求解旅行商问题。在现有的算法中,动态规划算法可以在O(n^2 * 2^n)的时间内解决问题,其中n是图中的节点数。分支切割算法已被应用于解决具有大量节点的问题。然而,分支切割算法也有一个指数最坏情况下的运行时间。本文提出了旅行商问题的一种新的精确算法。该算法可用于求解现实生活中的任意旅行商问题,算法的时间复杂度区间为(O(n^4),O(n^3 * 2^n)).这意味着在某些情况下,该算法可以在多项式时间内找到最优解,尽管该算法也具有指数最坏情况运行时间。换句话说,该算法告诉我们,并非所有旅行商问题的实例都需要指数时间来计算最优解。本文的算法不仅可以帮助我们更好地解决旅行商问题,而且可以帮助我们加深对NP完全问题和P之间关系的理解,因此,对旅行商问题和NP难问题的进一步研究具有重要意义。

英文摘要:

Traveling salesman problem is a NP-hard problem. Until now, researchers have not found a polynomial time algorithm for traveling salesman problem. Among the existing algorithms, dynamic programming algorithm can solve the problem in time O(n^2*2^n) where n is the number of nodes in the graph. The branch-and-cut algorithm has been applied to solve the problem with a large number of nodes. However, branch-and-cut algorithm also has an exponential worst-case running time. In this paper, a new exact algorithm for traveling salesman problem is proposed. The algorithm can be used to solve an arbitrary instance of traveling salesman problem in real life and the time complexity interval of the algorithm is (O(n^4), O(n^3*2^n)). It means that for some instances, the algorithm can find the optimal solution in polynomial time although the algorithm also has an exponential worst-case running time. In other words, the algorithm tells us that not all the instances of traveling salesman problem need exponential time to compute the optimal solution. The algorithm of this paper can not only assist us to solve traveling salesman problem better, but also can assist us to deepen the comprehension of the relationship between NP-complete and P. Therefore, it is considerable in the further research on traveling salesman problem and NP-hard problem.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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