1641. Colorful Tree

时间限制 3000 ms   内存限制 128 MB

There is a tree with $n$ nodes, each of which has a type of color represented by an integer, where the color of node $i$ is $c_i$.

The path between each two different nodes is unique, of which we define the value as the number of different colors appearing in it.

Calculate the sum of values of all paths on the tree that has $\frac{n(n-1)}{2}$ paths in total.

输入数据

The input contains multiple test cases.

For each test case, the first line contains one positive integers $n$, indicating the number of node. $(2 \leq n \leq 200000)$

Next line contains $n$ integers where the $i$-th integer represents $c_i$, the color of node $i$. $(1 \leq c_i \leq n)$

Each of the next $n - 1$ lines contains two positive integers $x, y$ $(1 \leq x, y \leq n, x \neq y)$, meaning an edge between node $x$ and node $y$.

It is guaranteed that these edges form a tree.

输出数据

For each test case, output "Case #$x$: $y$" in one line (without quotes), where $x$ indicates the case number starting from $1$ and $y$ denotes the answer of corresponding case.

样例输入

复制
3
1 2 1
1 2
2 3
6
1 2 1 3 2 1
1 2
1 3
2 4
2 5
3 6 \n
 · · \n
 · \n
 · \n
 \n
 · · · · · \n
 · \n
 · \n
 · \n
 · \n
 · \n

样例输出

复制
Case #1: 6
Case #2: 29    ·   · \n
    ·   ·  \n

提交

请先 登录

Source

2017 Multi-University Training Contest - Team 1

© 2025 FAQs Contact About