CF914E.Palindromes in a Tree
提高+/省选-
通过率:0%
时间限制:4.00s
内存限制:256MB
AC君温馨提醒
该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。
题目描述
You are given a tree (a connected acyclic undirected graph) of n vertices. Vertices are numbered from 1 to n and each vertex is assigned a character from a to t.
A path in the tree is said to be palindromic if at least one permutation of the labels in the path is a palindrome.
For each vertex, output the number of palindromic paths passing through it.
Note: The path from vertex u to vertex v is considered to be the same as the path from vertex v to vertex u, and this path will be counted only once for each of the vertices it passes through.
给你一棵树(一个连通的无环无向图),包含 n 个顶点。顶点编号从 1 到 n,每个顶点被赋予一个从 a 到 t 的字符。
若一条树上的路径中,其所有顶点标签的某种排列构成回文串,则称该路径为回文路径。
对每个顶点,输出经过该顶点的回文路径的数量。
注意:从顶点 u 到顶点 v 的路径与从顶点 v 到顶点 u 的路径视为同一条路径,且该路径对其所经过的每一个顶点仅计数一次。
输入格式
The first line contains an integer n (2 ≤ n ≤ 2·105) — the number of vertices in the tree.
The next n - 1 lines each contain two integers u and v (1 ≤ u, v ≤ n, u ≠ v) denoting an edge connecting vertex u and vertex v. It is guaranteed that the given graph is a tree.
The next line contains a string consisting of n lowercase characters from a to t where the i-th (1 ≤ i ≤ n) character is the label of vertex i in the tree.
第一行包含一个整数 n(2≤n≤2⋅105)—— 树中顶点的数量。
接下来的 n−1 行,每行包含两个整数 u 和 v(1≤u,v≤n, u=v),表示连接顶点 u 和顶点 v 的一条边。保证所给图是一棵树。
下一行包含一个由 n 个小写字母(从 a 到 t)组成的字符串,其中第 i 个字符(1≤i≤n)表示树中顶点 i 的标签。
输出格式
Print n integers in a single line, the i-th of which is the number of palindromic paths passing through vertex i in the tree.
在一行中输出 n 个整数,其中第 i 个整数表示树中经过顶点 i 的回文路径的数量。
输入输出样例
输入#1
5 1 2 2 3 3 4 3 5 abcbb
输出#1
1 3 4 3 3
输入#2
7 6 2 4 3 3 7 5 2 7 2 1 4 afefdfs
输出#2
1 4 1 1 2 4 2
说明/提示
In the first sample case, the following paths are palindromic:
2 - 3 - 4
2 - 3 - 5
4 - 3 - 5
Additionally, all paths containing only one vertex are palindromic. Listed below are a few paths in the first sample that are not palindromic:
1 - 2 - 3
1 - 2 - 3 - 4
1 - 2 - 3 - 5
在第一个样例中,以下路径是回文路径:
2 - 3 - 4
2 - 3 - 5
4 - 3 - 5
此外,所有仅包含一个顶点的路径均为回文路径。下面列出第一个样例中若干非回文路径:
1 - 2 - 3
1 - 2 - 3 - 4
1 - 2 - 3 - 5
输入解题思路,AI测评打分。不知道怎么写?