NaCl__的博客

Joke with permutation Time Limit: 3000ms, Special Time Limit:7500ms, Memory Limit:65536KB Total submit users: 87, Accepted users: 60 Problem 13341 : Special judge Problem description Joey had save

Judging Troubles Time Limit: 5000ms, Special Time Limit:12500ms, Memory Limit:65536KB Total submit users: 91, Accepted users: 72 Problem 13352 : No special judgement Problem description The NWERC

Cent Savings Time Limit: 5000ms, Special Time Limit:12500ms, Memory Limit:65536KB Total submit users: 59, Accepted users: 45 Problem 13345 : No special judgement Problem description To host a regi

题目链接http://acm.hnu.cn/online/?action=problem&type=show&id=13342&courseid=0 Problem description The races became more popular than ever at Pandora planet. But these races are quite unusual. There are n

对于背包问题，网上有很多博客= =，如果有不小心点进来的朋友，看到我挫逼的博文然后看不懂，可以自行百度一篇，其中本文的博文内 容参照 http://blog.youkuaiyun.com/lyhvoyage/article/details/8545852#0-qzone-1-46291-d020d2d2a4e8d1a374a433f596ad1440 那里讲的很详细 01背包问题 01背包问题的模型可以

Your current task is to make a ground plan for a residential building located in HZXJHS. So you must determine a way to split the floor building with walls to make apartments in the shape of a rectangl

Problem DescriptionThere are n apple trees planted along a cyclic road, which is L metres long. Your storehouse is built at position 0 on that cyclic road. The ith tree is planted at position xi, clo

给出一个只有01的字符串，请找出最长的的01的数目的相等的字串。。这题最暴力的解决方法就是就是先预处理每个区间01的数目，然后枚举起点和重点，时间复杂度是O(N^2)。下面我们来介绍一种O(n)时间复杂度的做法。。。首先我们可以用一个数组B[i]把串A当中A[0...i]中1和0的差存起来。这样我们能发现符合要求的就是串满足B[i]==B[j].题目要要最最长，然后找到i-j跨度最大的

这题先求出最小生成树，然后在最小生成树中求任意两个点之和的平均数。。因为最小生成树是唯一的，所以期望也就只有一个。求最小生成树的时候把树存起来。求任意两点之和的时候我们求出一条边在求和的时候用了多少次，也就是求该边的左右端点有多少个比如一条边左右两边有A，B个端点，那么利用的次数也就是A*B。 我们可以用dfs来实现，用sum数组表示k点子树上的点（包括他自己）,那么kf父亲那边的点就是n-sum