优化递归式处理:最大划分性质与Berlekamp-Massey算法在信息学竞赛中的应用

需积分: 0 271 下载量 127 浏览量 更新于2024-08-09 收藏 2.84MB PDF 举报
"《最大划分的性质 - ANSI/VITA 62-2016 模块化电源供应标准》探讨了在信息技术领域中的一个重要问题,即如何优化算法性能,特别是在处理字符串分割问题上。原有的算法(算法一和算法二)由于涉及三个串的子串枚举,其时间复杂度至少达到O(n^6)。文章的核心内容聚焦于通过挖掘最大划分的性质,将三个子串的搜索分解,从而降低复杂度。 主要结论是,对于给定字符串S,一个划分(X1, Y1, Z1)被认为是S的最大划分,当且仅当满足两个条件:1) Y1和Z1的组合不是X的连续子串;2) Z1不是Y的连续子串。这里,空串表示为`�`,连续子串表示为`S[i:j]`。通过反证法证明了这些性质的重要性,即如果这两个条件不满足,那么总能找到一个更大的划分。 这个发现对优化字符串处理算法具有实际意义,特别是在处理像最大划分这样的问题时,可以减少搜索空间,提高算法效率。它涉及到的理论基础包括递归结构和复杂度分析,对于竞赛选手来说,理解并应用这些性质可以帮助他们在信息学竞赛中解决更高效的问题。 文章的背景是2017年中国国家集训队论文集,展示了递归多项式和Berlekamp-Massey算法在信息学竞赛中的潜在应用。递归多项式是一个创新的概念,用于处理隐式递归式,而Berlekamp-Massey算法尽管鲜为人知,但其实是个强大的工具,可用于计算数列的特征多项式等复杂问题。作者希望通过对这两个主题的深入探讨,让读者了解它们的理论价值和实际应用场景,从而提升参赛者的竞争力。"
2020-02-06 上传
VITA 62-2016 英文原版标准,带目录。 VITA 62 defines both the mechanical and electrical requirements for COTS modules intended for creating modular power supplies. The primary focus is to support [VITA 46.0] and [VITA 65] systems with off the shelf modules that are compatible with the VPX specifications. The embedded market has focused primarily on the need to standardize the use of COTS processing add-in modules as part of the VPX suite of standards. Before this standard system designers treated the power supply as a necessary evil, which is often an afterthought. Modular power supply suppliers provided ad hoc solutions that system developers must implement. Providing power for these systems had historically been left up the module vendor, requiring them to define what has, at times, been seen as a form of “black art.” This standard, however, defines a set of rules by which industry power supply vendors can build COTS products, for VPX systems, that will fit into VITA 62 compatible backplanes. Consequently, system developers can have multiple vendors for power supply modules. At this time the focus of this standard is to define modules for VPX systems. In the future this standard may also be extended into other form factors. As part of the work to create VITA 62, a new connector system has been defined, optimized for the needs of VITA 62. This connector mechanically fits within the envelope defined in [VITA 46.0] for 3U and 6U Plug-In modules. This will facilitate the production of backplanes and allow system designers to define where and how many power supply modules are to be used within any given system.