C. Paint Tree time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given a tree with n vertexes and n points on a plane, no three points lie on one straight line. Your task is to paint…

A. Plate Game 如果可以放置一个圆的情况下,先手将圆放置在矩形正中心,那么根据对称性,先手只要放后手的对称的位置即可,也就是先手必胜,否则后手胜. B. Limit 讨论\(n,m\)的大小关系. 虚拟场时当\(n \gt m\)的情况写错了,应该根据\(a_0b_0\)的正负性判断是正无穷还是负无穷. C. Lexicographically Maximum Subsequence 从后往前扫,递增的取. D. Infinite Maze 假设原地图为\(M\),则扩展成\[MM\…

题目链接:https://codeforces.com/contest/1244/problem/D 题意:给你一个树,让你把树上的每个节点染成三种颜色,使得任意三个互相相邻的节点颜色都不一样(意思是如果两个节点相邻,那么与这两个节点相邻的节点的颜色得和这两个节点都不一样).这里给出每个节点染成三种颜色的代价,让我们求全部染色代价最小的方案与最小代价. 解析:如果一个点的度数大于等于3,那么肯定没有方案.所有这个树一定只是一条链,我们从度数为1的点开始dfs,把这条链存在数组里,就相当于我们只需…

D. Happy Tree Party Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/593/problem/D Description Bogdan has a birthday today and mom gave him a tree consisting of n vertecies. For every edge of the tree i, some number xi was w…

D. Happy Tree Party     Bogdan has a birthday today and mom gave him a tree consisting of n vertecies. For every edge of the tree i, some number xi was written on it. In case you forget, a tree is a connected non-directed graph without cycles. After…

C. Propagating tree Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/383/problem/C Description Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numb…

D. Water Tree Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/343/problem/D Description Mad scientist Mike has constructed a rooted tree, which consists of n vertices. Each vertex is a reservoir which can be either empty or…

F. st-Spanning Tree 题目连接: http://codeforces.com/contest/723/problem/F Description You are given an undirected connected graph consisting of n vertices and m edges. There are no loops and no multiple edges in the graph. You are also given two distinct…

C. Propagating tree Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/383/problem/C Description Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numb…

Water Tree 给出一棵树,有三种操作: 1 x:把以x为子树的节点全部置为1 2 x:把x以及他的所有祖先全部置为0 3 x:询问节点x的值 分析: 昨晚看完题,马上想到直接树链剖分,在记录时间戳时需要记录一下出去时的时间戳,然后就是很裸很裸的树链剖分了. 稳稳的黄名节奏,因为一点私事所以没做导致延迟了 (ps:后来想了一下,不用树链剖分直接dfs序维护也行...) #include <set> #include <map> #include <list> #i…