随笔分类 -  题库 - poj

摘要：题目描述 $T$ 组询问，用 $n$ 种颜色去染 $n$ 个点的环，旋转后相同视为同构。求不同构的环的个数模 $p$ 的结果。 $T\le 3500,n\le 10^9,p\le 30000$ 。 题解 Polya定理+欧拉函数 根据 poj2409 中得到的结论，答案为： $\frac{\sum\ 阅读全文

摘要：题目描述 用 $c$ 种颜色去染 $r$ 个点的环，如果两个环在旋转或翻转后是相同的，则称这两个环是同构的。求不同构的环的个数。 $r·c\le 32$ 。 题解 Polya定理 Burnside引理：一个置换群的等价类数目等于这个置换群中所有置换的不动点数目的平均值；Polya定理：设有限群G有 阅读全文

摘要：题目描述 Give a tree with n vertices,each edge has a length(positive integer less than 1001). Define dist(u,v)=The min distance between node u and v. Give 阅读全文

摘要：题目描述 You are working for Macrohard company in data structures department. After failing your previous task about key insertion you were asked to write 阅读全文

摘要：题目描述 Ivan is fond of collecting. Unlike other people who collect post stamps, coins or other material stuff, he collects software bugs. When Ivan gets 阅读全文