Codeforces Round 525 (Div. 2)
E
Ehab and a component choosing problem
Codeforces
2400
原题
← DF →
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You're given a tree consisting of $n$ nodes. Every node $u$ has a weight $a_u$. You want to choose an integer $k$ $(1 \le k \le n)$ and then choose $k$ connected components of nodes that don't overlap (i.e every node is in at most 1 component). Let the set of nodes you chose be $s$. You want to maximize:

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$$\frac{\sum\limits_{u \in s} a_u}{k}$$

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In other words, you want to maximize the sum of weights of nodes in $s$ divided by the number of connected components you chose. Also, if there are several solutions, you want to maximize $k$.

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Note that adjacent nodes can belong to different components. Refer to the third sample.

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Input

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The first line contains the integer $n$ $(1 \le n \le 3 \cdot 10^5)$, the number of nodes in the tree.

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The second line contains $n$ space-separated integers $a_1$, $a_2$, $\dots$, $a_n$ $(|a_i| \le 10^9)$, the weights of the nodes.

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The next $n-1$ lines, each contains 2 space-separated integers $u$ and $v$ $(1 \le u,v \le n)$ which means there's an edge between $u$ and $v$.

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Output

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Print the answer as a non-reduced fraction represented by 2 space-separated integers. The fraction itself should be maximized and if there are several possible ways, you should maximize the denominator. See the samples for a better understanding.

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Note

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A connected component is a set of nodes such that for any node in the set, you can reach all other nodes in the set passing only nodes in the set.

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In the first sample, it's optimal to choose the whole tree.

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In the second sample, you only have one choice (to choose node 1) because you can't choose 0 components.

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In the third sample, notice that we could've, for example, chosen only node 1, or node 1 and node 3, or even the whole tree, and the fraction would've had the same value (-1), but we want to maximize $k$.

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In the fourth sample, we'll just choose nodes 1 and 3.

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样例

Input #1
3
1 2 3
1 2
1 3
Output #1
6 1
InputCopy OutputCopy
Input #2
1
-2
Output #2
-2 1
InputCopy OutputCopy
Input #3
3
-1 -1 -1
1 2
2 3
Output #3
-3 3
InputCopy OutputCopy
Input #4
3
-1 -2 -1
1 2
1 3
Output #4
-2 2
InputCopy OutputCopy
题目信息
题号
1088E
时间限制
1 s
内存限制
256 MB
标签
动态规划
贪心
数学
树

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