CF825G.Tree Queries

普及/提高-

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题目描述

You are given a tree consisting of nn vertices (numbered from 11 to nn ). Initially all vertices are white. You have to process qq queries of two different types:

  1. 11 xx — change the color of vertex xx to black. It is guaranteed that the first query will be of this type.
  2. 22 xx — for the vertex xx , find the minimum index yy such that the vertex with index yy belongs to the simple path from xx to some black vertex (a simple path never visits any vertex more than once).

For each query of type 22 print the answer to it.

Note that the queries are given in modified way.

输入格式

The first line contains two numbers nn and qq ( 3<=n,q<=1063<=n,q<=10^{6} ).

Then n1n-1 lines follow, each line containing two numbers xix_{i} and yiy_{i} ( 1<=x_{i}<y_{i}<=n ) and representing the edge between vertices xix_{i} and yiy_{i} .

It is guaranteed that these edges form a tree.

Then qq lines follow. Each line contains two integers tit_{i} and ziz_{i} , where tit_{i} is the type of ii th query, and ziz_{i} can be used to restore xix_{i} for this query in this way: you have to keep track of the answer to the last query of type 22 (let's call this answer lastlast , and initially last=0last=0 ); then xi=(zi+last)modn+1x_{i}=(z_{i}+last)modn+1 .

It is guaranteed that the first query is of type 11 , and there is at least one query of type 22 .

输出格式

For each query of type 22 output the answer to it.

输入输出样例

  • 输入#1

    4 6
    1 2
    2 3
    3 4
    1 2
    1 2
    2 2
    1 3
    2 2
    2 2
    

    输出#1

    3
    2
    1
    
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