#P9847. [ICPC2021 Nanjing R] Crystalfly

    ID: 9204 远端评测题 2000ms 256MiB 尝试: 0 已通过: 0 难度: 5 上传者: 标签>动态规划,dp2021Special JudgeO2优化树形 dpICPC南京

[ICPC2021 Nanjing R] Crystalfly

题目描述

Paimon is catching crystalflies on a tree, which are a special kind of butterflies in Teyvat. A tree is a connected graph consisting of nn vertices and (n1)(n - 1) undirected edges.

There are initially aia_i crystalflies on the ii-th vertex. When Paimon reaches a vertex, she can catch all the remaining crystalflies on the vertex immediately. However, the crystalflies are timid. When Paimon reaches a vertex, all the crystalflies on the adjacent vertices will be disturbed. For the ii-th vertex, if the crystalflies on the vertex are disturbed for the first time at the beginning of the tt'-th second, they will disappear at the end of the (t+ti)(t' + t_{i})-th second.

At the beginning of the 00-th second, Paimon reaches vertex 11 and stays there before the beginning of the 11-st second. Then at the beginning of each following second, she can choose one of the two operations:

  • Move to one of the adjacent vertices of her current vertex and stay there before the beginning of the next second (if the crystalflies in the destination will disappear at the end of that second she can still catch them).
  • Stay still in her current vertex before the beginning of the next second.

Calculate the maximum number of crystalflies Paimon can catch in 101010101010^{10^{10^{10^{10}}}} seconds.

输入格式

There are multiple test cases. The first line of the input contains an integer TT indicating the number of test cases. For each test case:

The first line contains an integer nn (1n1051 \le n \le 10^5) indicating the number of vertices.

The second line contains nn integers a1,a2,,ana_1, a_2, \cdots, a_n (1ai1091 \le a_i \le 10^9) where aia_i is the number of crystalflies on the ii-th vertex.

The third line contains nn integers t1,t2,,tnt_1, t_2, \cdots, t_n (1ti31 \le t_i \le 3) where tit_i is the time before the crystalflies on the ii-th vertex disappear after disturbed.

For the next (n1)(n - 1) lines, the ii-th line contains two integers uiu_i and viv_i (1ui,vin1 \le u_i, v_i \le n) indicating an edge connecting vertices uiu_i and viv_i in the tree.

It's guaranteed that the sum of nn of all the test cases will not exceed 10610^6.

输出格式

For each test case output one line containing one integer indicating the maximum number of crystalflies Paimon can catch.

题目大意

给定一个 n(1n105)n(1\le n\le10^5) 个节点的树,每个节点上有 aia_i 只晶蝶。派蒙最初在 11 号节点,并获得 11 号节点的所有晶蝶,接下来每一秒她可以移动到相邻的节点上并获得节点上的所有晶蝶,但是当她每到达一个节点 uu 后,对于每个与 uu 相邻的节点 vv,节点 vv 上的的晶蝶会在 tv(1tv3)t_v(1\le t_v\le3) 秒内消失,在 tvt_v 秒后再到达节点 vv 将无法获得节点上的晶蝶。现在需要你求出最多可以获得的晶蝶数。

2
5
1 10 100 1000 10000
1 2 1 1 1
1 2
1 3
2 4
2 5
5
1 10 100 1000 10000
1 3 1 1 1
1 2
1 3
2 4
2 5

10101
10111

提示

For the first sample test case, follow the strategy below.

  • During the 00-th second
    • Paimon arrives at vertex 11;
    • Paimon catches 11 crystalfly;
    • Crystalflies in vertices 22 and 33 are disturbed.
  • During the 11-st second
    • Paimon arrives at vertex 33;
    • Paimon catches 100100 crystalflies.
  • During the 22-nd second
    • Paimon arrives at vertex 11;
    • Crystalflies in vertex 22 disappears.
  • During the 33-rd second
    • Paimon arrives at vertex 22;
    • Crystalflies in vertices 44 and 55 are disturbed.
  • During the 44-th second
    • Paimon arrives at vertex 55;
    • Paimon catches 1000010000 crystalflies;
    • Crystalflies in vertex 44 disappears.

For the second sample test case, the optimal strategy is the same with the first sample test case. Crystalflies in vertex 22 are scheduled to disappear at the end of the 33-rd (instead of the 22-nd) second, allowing Paimon to catch them.