QTREE5 - Query on a tree V


You are given a tree (an acyclic undirected connected graph) with N nodes. The tree nodes are numbered from 1 to N. We define dist(a, b) as the number of edges on the path from node a to node b.

Each node has a color, white or black. All the nodes are black initially.

We will ask you to perform some instructions of the following form:

  • 0 i : change the color of i-th node(from black to white, or from white to black).
  • 1 v : ask for the minimum dist(u, v), node u must be white(u can be equal to v). Obviously, as long as node v is white, the result will always be 0.

Input

  • In the first line there is an integer N (N <= 100000)
  • In the next N-1 lines, the i-th line describes the i-th edge: a line with two integers a b denotes an edge between a and b.
  • In the next line, there is an integer Q denotes the number of instructions (Q <= 100000)
  • In the next Q lines, each line contains an instruction "0 i" or "1 v"

Output

For each "1 v" operation, print one integer representing its result. If there is no white node in the tree, you should write "-1".

Example

Input:
10
1 2
1 3
2 4
1 5
1 6
4 7
7 8
5 9
1 10
10
0 6
0 6
0 6
1 3
0 1
0 1
1 3
1 10
1 4
1 6

Output:
2
2
2
3
0

hide comments
mestu_paul: 2023-11-02 07:16:17

yeah it is spoj, that's why i didn't got AC in one submission
1st compilation error for wrong compiler selection,
2nd for extra print (for debug)
3rd is accepted , yes

sleepntsheep: 2023-09-02 08:03:53

O(N * lg(N) + Q * lg(N)^2)) TLE :(

Last edit: 2023-09-02 08:08:07
saiprasad_27: 2022-06-20 01:27:04

mine using Centroid decomposition and multiset passed in 1.25secs when the time limit being 1s:).
any better way of doing it ???

nafis_shahriar: 2021-07-06 09:05:54

@cichipi_ Thanks, didn't know that about multiset.

mhasan01: 2020-07-12 01:23:35

Finally got Accepted :')

kinhosz: 2020-01-18 00:09:45

I know how to solve it using hld

tanmayak99: 2019-12-12 09:55:46

Don't use "long long int" -> gave me TLE

hocky: 2019-04-20 16:26:51

When decomposing the tree (checking the tree subsize and traversing centroid), remember not to go back to the ones that has been in the decomposed tree

Last edit: 2019-04-20 16:27:57
cichipi_: 2018-10-25 10:45:58

remember ......
your multiset ms = {1,1,1,3,4}
after calling ms.erase(1) it will be = {3,4}
so do this,
auto it = ms.find(1) ;
ms.erase(it);

got 3 WA for this crap :)

Last edit: 2018-10-25 10:46:14
cichipi_: 2018-10-25 08:32:49

Time limit not even 1s....fuck


Added by:Qu Jun
Date:2008-08-13
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:XunYunbo, modified from ZJOI07