传送门:http://codeforces.com/contest/1092/problem/F F. Tree with Maximum Cost time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given a tree consisting exactly of nn vertices. Tree is a…

CF1324 --- Maximum White Subtree 题干 You are given a tree consisting exactly of \(n\) vertices. Tree is a connected undirected graph with \(n−1\) edges. Each vertex \(v\) of this tree has a value \(a_v\) assigned to it. Let \(dist(x,y)\) be the distan…

Big Christmas Tree Time Limit: 3000MS   Memory Limit: 131072K Total Submissions: 23387   Accepted: 5063 Description Christmas is coming to KCM city. Suby the loyal civilian in KCM city is preparing a big neat Christmas tree. The simple structure of t…

Color a Tree Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 828    Accepted Submission(s): 272 Problem DescriptionBob is very interested in the data structure of a tree. A tree is a directed gr…

http://poj.org/problem?id=3013 Big Christmas Tree Time Limit: 3000MS   Memory Limit: 131072K Total Submissions: 19009   Accepted: 4048 Description Christmas is coming to KCM city. Suby the loyal civilian in KCM city is preparing a big neat Christmas…

Big Christmas Tree Time Limit: 3000MS   Memory Limit: 131072K Total Submissions: 20974   Accepted: 4535 Description Christmas is coming to KCM city. Suby the loyal civilian in KCM city is preparing a big neat Christmas tree. The simple structure of t…

Big Christmas Tree Time Limit: 3000MS   Memory Limit: 131072K Total Submissions: 25823   Accepted: 5577 Description Christmas is coming to KCM city. Suby the loyal civilian in KCM city is preparing a big neat Christmas tree. The simple structure of t…

题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=3071 题目大意: 给定一个长度为n的序列m次操作,操作的种类一共有三种 查询 L :查询一个区间的所有的数的最小公倍数modp G :查询一个区间的所有的数的最大公约数modp 修改 C :将给定位置的值修改成x 解题思路: 注意数据范围,每个数字不超过100,所以100以内的质因子最多25个,如果直接求解lcm和gcd的话,long long也是存不下的,所以采用存储质因子的指数,但是如果每个节…

给出一棵树,边有权值,求出离每一个节点最远的点的距离 树形DP,经典题 本来这道题是无根树,可以随意选择root, 但是根据输入数据的方式,选择root=1明显可以方便很多. 我们先把边权转化为点权,放在数组cost中 令tree(i)表示以节点i为根的子树 对于节点i,离该节点最远的点要不就是在tree(i)中,要不就是在father(i)上面 令: dp[i][1] : 在子树tree(i)中,离i最远的距离 dp[i][2] : 在子树tree(i)中,离i第二远的距离 (递推的时候需要)…

Road 题目链接: http://acm.split.hdu.edu.cn/showproblem.php?pid=5861 Description There are n villages along a high way, and divided the high way into n-1 segments. Each segment would charge a certain amount of money for being open for one day, and you can…