CF1787G.Colorful Tree Again

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题目描述

An edge-weighted tree of nn nodes is given with each edge colored in some color. Each node of this tree can be blocked or unblocked, all nodes are unblocked initially.

A simple path is a path in a graph that does not have repeating nodes. The length of a path is defined as the sum of weights of all edges on the path.

A path is good when it is a simple path consisting of edges of the same color cc , all edges of color cc are on this path, and every node on the path is unblocked.

You need to operate 22 kinds of queries:

  1. block a node,
  2. unblock a node.

After each query, print the maximum length among all good paths. If there are no good paths, print 00 .

输入格式

The first line contains two integers nn , qq ( 1n,q21051 \leq n,q \leq 2\cdot 10^5 ) — the number of nodes and the number of queries.

Then n1n-1 lines follow, each containing four integers uu , vv , ww and cc ( 1u,v,w,cn1 \leq u,v,w,c \leq n ; uvu \not = v ), denoting a weighted edge connecting node uu and node vv with weight ww and color cc . It is guaranteed that these edges form a tree.

Then qq lines follow, each containing two integers pp and xx ( p=0p = 0 or p=1p = 1 , 1xn1\leq x\leq n ), denoting a query:

  1. if p=0p = 0 , block the node xx . It's guaranteed that it's not blocked at this time;
  2. if p=1p = 1 , unblock the node xx . It's guaranteed that it's blocked at this time.

输出格式

For each query, print the maximum length of a good path. If there are no good paths, print 00 .

输入输出样例

  • 输入#1

    5 4
    4 1 3 4
    5 2 4 4
    3 1 3 2
    1 2 5 1
    0 4
    0 3
    0 2
    1 3

    输出#1

    5
    5
    0
    3
  • 输入#2

    5 5
    4 1 4 4
    4 5 2 2
    3 1 2 4
    3 2 3 1
    0 3
    0 4
    1 3
    1 4
    0 1

    输出#2

    2
    0
    3
    6
    3
  • 输入#3

    6 9
    3 2 2 3
    2 4 4 2
    3 1 5 5
    6 4 3 2
    5 3 1 3
    0 2
    0 4
    0 5
    0 6
    1 2
    1 4
    1 5
    0 3
    1 6

    输出#3

    5
    5
    5
    5
    5
    5
    5
    0
    7
  • 输入#4

    1 2
    0 1
    1 1

    输出#4

    0
    0
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