Codeforces Round 848 (Div. 2)
F
Maximizing Root
Codeforces
2600
原题
← E→
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You are given a rooted tree consisting of $n$ vertices numbered from $1$ to $n$. Vertex $1$ is the root of the tree. Each vertex has an integer value. The value of $i$-th vertex is $a_i$. You can do the following operation at most $k$ times.

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  • Choose a vertex $v$ that has not been chosen before and an integer $x$ such that $x$ is a common divisor of the values of all vertices of the subtree of $v$. Multiply by $x$ the value of each vertex in the subtree of $v$.
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What is the maximum possible value of the root node $1$ after at most $k$ operations? Formally, you have to maximize the value of $a_1$.

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A tree is a connected undirected graph without cycles. A rooted tree is a tree with a selected vertex, which is called the root. The subtree of a node $u$ is the set of all nodes $y$ such that the simple path from $y$ to the root passes through $u$. Note that $u$ is in the subtree of $u$.

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Input

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The first line contains an integer $t$ ($1 \leq t \leq 50\,000$) — the number of test cases. The description of the test cases follows.

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The first line of each test case contains two integers $n$ and $k$ ($2 \leq n \leq 10^5$, $0 \leq k \leq n$) — the number of vertices in the tree and the number of operations.

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The second line contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \leq a_i \leq 1000$), where $a_i$ denotes the value of vertex $i$.

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Each of the next $n - 1$ lines contains two integers $u_i$ and $v_i$ ($1 \leq u_i, v_i \leq n$, $u_i \neq v_i$), denoting the edge of the tree between vertices $u_i$ and $v_i$. It is guaranteed that the given edges form a tree.

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It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.

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Output

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For each test case, output the maximum value of the root after performing at most $k$ operations.

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Note

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Both examples have the same tree:

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image

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For the first test case, you can do two operations as follows:

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  • Choose the subtree of vertex $4$ and $x = 2$. image After this operation, the node values become $\{24, 12, 24, 12, 12\}.$
  • Choose the subtree of vertex $1$ and $x = 12$. image After this operation, the node values become $\{288, 144, 288, 144, 144\}.$
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The value of the root is $288$ and it is the maximum.

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For the second test case, you can do three operations as follows:

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  • Choose the subtree of vertex $4$ and $x = 2$. image After this operation, the node values become $\{24, 12, 24, 12, 12\}.$
  • Choose the subtree of vertex $2$ and $x = 4$. image After this operation, the node values become $\{24, 48, 24, 48, 48\}.$
  • Choose the subtree of vertex $1$ and $x = 24$. image After this operation, the node values become $\{576, 1152, 576, 1152, 1152\}.$
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The value of the root is $576$ and it is the maximum.

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样例

Input #1
2
5 2
24 12 24 6 12
1 2
1 3
2 4
2 5
5 3
24 12 24 6 12
1 2
1 3
2 4
2 5
Output #1
288
576
InputCopy OutputCopy
题目信息
题号
1778F
时间限制
2 s
内存限制
1024 MB
标签
DFS 及类似
动态规划
图论
数学
数论
树

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