题目描述 Farmer John continues his never-ending quest to keep the cows fit by having them exercise on various cow paths that run through the pastures. These cow paths can be represented as a set of vertices connected with bidirectional edges so that each…

题目链接 二分答案,判断需要断几条边,用\(f[i]\)表示以\(i\)为根的子树断边后的最长路径,对于一个点\(u\),存在\(f[v]>mid\)时就删到\(v\)的边\(f[v1]+f[v2]>mid\)时就删\(f\)较大的边,可以sort之后搞一搞 #include<algorithm> #include<iostream> #include<cstring> #include<cstdio> #include<vector>…

P2853 [USACO06DEC]牛的野餐Cow Picnic 你愿意的话,可以写dj. 然鹅,对一个缺时间的退役选手来说,暴力模拟是一个不错的选择. 让每个奶牛都把图走一遍,显然那些被每个奶牛都走过的点就是符合条件的点. #include<iostream> #include<cstdio> #include<cstring> using namespace std; #define N 1002 int val[N],in[N],k,n,m,ans; bool d…

P2909 [USACO08OPEN]牛的车Cow Cars 显然的贪心. 按速度从小到大排序.然后找车最少的车道,查询是否能填充进去. #include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define re register using namespace std; ],d[]; int main(){ scanf("%d%d%d%d",&…

P2906 [USACO08OPEN]牛的街区Cow Neighborhoods 考虑维护曼哈顿距离:$\left | x_{1}-x_{2} \right |+\left | y_{1}-y_{2} \right |$ 看起来很难维护的样子,我们尝试转化 设两个点$(x_{1},y_{1}),(x_{2},y_{2})  (x_{1}>=x_{2})$ 那么它们的曼哈顿距离有2种情况 1.$y_{1}>y_{2}:\left | x_{1}-x_{2} \right |+\left | y_…

P1821 [USACO07FEB]银牛派对Silver Cow Party 题目描述 One cow from each of N farms (1 ≤ N ≤ 1000) conveniently numbered 1..N is going to attend the big cow party to be held at farm #X (1 ≤ X ≤ N). A total of M (1 ≤ M ≤ 100,000) unidirectional (one-way roads co…

P2966 [USACO09DEC]牛收费路径Cow Toll Paths 题目描述 Like everyone else, FJ is always thinking up ways to increase his revenue. To this end, he has set up a series of tolls that the cows will pay when they traverse the cowpaths throughout the farm. The cows mo…

---恢复内容开始--- P1522 牛的旅行 Cow Tours189通过502提交题目提供者该用户不存在标签 图论 USACO难度 提高+/省选-提交该题 讨论 题解 记录 最新讨论 输出格式题目描述 农民 John的农场里有很多牧区.有的路径连接一些特定的牧区.一片所有连通的牧区称为一个牧场.但是就目前而言,你能看到至少有两个牧区通过任何路径都不连通.这样,Farmer John就有多个牧场了. John想在牧场里添加一条路径(注意,恰好一条).对这条路径有以下限制: 一个牧场的直径就是牧…

P2971 [USACO10HOL]牛的政治Cow Politics 农夫约翰的奶牛住在N (2 <= N <= 200,000)片不同的草地上,标号为1到N.恰好有N-1条单位长度的双向道路,用各种各样的方法连接这些草地.而且从每片草地出发都可以抵达其他所有草地.也就是说,这些草地和道路构成了一种叫做树的图.输入包含一个详细的草地的集合,详细说明了每个草地的父节点P_i (0 <= P_i <= N).根节点的P_i == 0, 表示它没有父节点.因为奶牛建立了1到K一共K (1…

版权声明:本文为博主原创文章,未经博主同意不得转载. https://blog.csdn.net/u012515223/article/details/37909933 最好牛线(Best Cow Line) 代码(C) 本文地址: http://blog.csdn.net/caroline_wendy 题目: 给定长度为N的字符串S, 要构造一个长度为N的字符串T. 重复进行例如以下随意操作. 从S的头部删除一个字符, 放入T的尾部; 从S的尾部删除一个字符, 放入T的尾部; 目标是要构造字典…