Alyona and a tree time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Alyona has a tree with n vertices. The root of the tree is the vertex 1. In each vertex Alyona wrote an positive integer,…

time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output Alyona has a tree with n vertices. The root of the tree is the vertex 1. In each vertex Alyona wrote an positive integer, in the vertex i she wr…

题目链接: C. Alyona and the Tree time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Alyona decided to go on a diet and went to the forest to get some apples. There she unexpectedly found a magic r…

Alyona and the Tree Descriptions 小灵决定节食,于是去森林里摘了些苹果.在那里,她意外地发现了一棵神奇的有根树,它的根在节点 1 上,每个节点和每条边上都有一个数字. 小灵注意到树上有一些节点不开心,所以她决定和它们一起玩. 如果节点 v 的子树中有一个节点 u 使得dist(v, u) > au ,那么节点 v 就会不开心.au 代表节点 u 上的数字,dist(v, u)代表连接节点 v 到节点 u 的所有边上的数字和,也就是两个节点的距离. 通过 1 条边连…

[链接] 我是链接,点我呀:) [题意] 题意 [题解] 设dis[v]表示v以上的点到达这个点的最大权值(肯定是它的祖先中的某个点到这个点) 类似于最大连续累加和 当往下走(x,y)这条边的时候,设其权值为w,以及到目前为止走过的最大权值和cur 如果cur<0,那么就不要之前的路径了,直接加上cur. 否则连着之前的路径加上去就好. 这样就能贪心地求出来dis[v]了 如果dis[x]>a[x]那么它以及它下面的所有节点都要删掉(因为要从叶子节点开始删) 如果dis[x]<=a[x]…

题目链接: http://codeforces.com/contest/740/problem/D D. Alyona and a tree time limit per test2 secondsmemory limit per test256 megabytes 问题描述 Alyona has a tree with n vertices. The root of the tree is the vertex 1. In each vertex Alyona wrote an positiv…

B. Alyona and a tree 题目连接: http://codeforces.com/contest/739/problem/B Description Alyona has a tree with n vertices. The root of the tree is the vertex 1. In each vertex Alyona wrote an positive integer, in the vertex i she wrote ai. Moreover, the g…

D. Alyona and a tree time limit per test  2 seconds memory limit per test  256 megabytes input  standard input output  standard output Alyona has a tree with n vertices. The root of the tree is the vertex 1. In each vertex Alyona wrote an positive in…

D. Alyona and a tree Problem Description: Alyona has a tree with n vertices. The root of the tree is the vertex 1. In each vertex Alyona wrote an positive integer, in the vertex i she wrote ai. Moreover, the girl wrote a positive integer to every edg…

D. Alyona and a tree time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Alyona has a tree with n vertices. The root of the tree is the vertex 1. In each vertex Alyona wrote an positive intege…