不难发现为了逐步确定每个点于其相邻点的相交情况,那么我们只可能有两种逐步构造的方式:从根开始往下构造,以及从子树往根上构造.经过很久的尝试,我发现从根往下构造是一件很困难的事情,于是我们可以反过来考虑第二种构造方式. 既然是从子树开始构造,那么我们先想一下最底层是如何构造的.不难发现最底层实质上是一个菊花图的形式,因为父亲和这些儿子必然有交,那么这些儿子之间一定也会有交,为了让儿子之间不会互相连边,我们只能让所有儿子区间一个包含另一个.为了方便起见,我们让所有儿子的区间和父亲区间的交在左端点,大…

The Three Laws of TDD First Law : you may not write production code until you have written a failing unit test. Second Law : you may not write more of a unit test than is sufficient to fail, and not compiling is failing. Third Law : you may not write…

Shuffle Hashing A and B Berry Jam Segment Tree Tests for problem D Cards Shuffle Hashing \[ Time Limit: 2 s\quad Memory Limit: 256 MB \] 处理出 \(s_1\) 中各个字符出现的次数,然后双指针维护 \(s_2\) 中每一段长度为 \(len(s_1)\) 的串中字符出现的次数,如果存在某一段和 \(s_1\) 的字符次数相同,则是答案. view #inclu…

记录 Codeforces 2019年12月19日到 2020年2月12日 的部分比赛题 Educational Codeforces Round 82 (Rated for Div. 2) D Fill The Bag 给出m(≤1e5)个盒子,盒子的大小是2的幂次.可以选择把一个盒子分成大小相同的两部分,问最少执行几次分盒子的操作,可以装满大小为n(≤1e18)的背包. 把n转化为二进制,代表可以由若干种2的幂次的盒子各一个装满.从小往大贪心地使用已有的盒子,不足时把第一个比它大的盒子分开.…

https://code.google.com/codejam/contest/619102/dashboard#s=p1&a=1 Problem Now that you have won Code Jam and been hired by Google as a software engineer, you have been assigned to work on their wildly popular programming contest website. Google is ex…

If you write unit tests and use NUnit test framework this may be helpful. I decided to write this simple step by step project configuration because I tend to set it up on every new project but keep forgetting all its details of how to do this. Settin…

Problem about GCD Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 470    Accepted Submission(s): 77 Problem Description Given integer m. Find multiplication of all 1<=a<=m such gcd(a, m)=1 (cop…

rt 稳定婚姻匹配问题 The Stable Marriage Problem Time Limit: 5000/1000 MS (Java/Others)    Memory Limit: 65535/32768 K (Java/Others) Total Submission(s): 438    Accepted Submission(s): 222 Problem Description The stable marriage problem consists of matching m…

[题目] Tree chain problem Problem Description Coco has a tree, whose vertices are conveniently labeled by 1,2,-,n.There are m chain on the tree, Each chain has a certain weight. Coco would like to pick out some chains any two of which do not share comm…

The Stable Marriage Problem   Description The stable marriage problem consists of matching members of two different sets according to the member's preferences for the other set's members. The input for our problem consists of: a set M of n males; a s…