CF1796E.Colored Subgraphs

普及/提高-

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题目描述

Monocarp has a tree, consisting of nn vertices.

He is going to select some vertex rr and perform the following operations on each vertex vv from 11 to nn :

  • set dvd_v equal to the distance from vv to rr (the number of edges on the shortest path);
  • color vv some color.

A nice coloring satisfies two conditions:

  • for each pair of vertices of the same color (v,u)(v, u) , there exists a path from vv to uu that only visits vertices of the same color;
  • for each pair of vertices of the same color (v,u)(v, u) , dvdud_v \neq d_u .

Note that Monocarp can choose any amount of different colors he wants to use.

For each used color, he then counts the number of vertices of this color. The cost of the tree is the minimum of these numbers.

What can be the maximum cost of the tree?

输入格式

The first line contains a single integer tt ( 1t1041 \le t \le 10^4 ) — the number of testcases.

The first line of each testcase contains a single integer nn ( 3n21053 \le n \le 2 \cdot 10^5 ) — the number of vertices in the tree.

Each of the next n1n-1 lines contains two integers vv and uu ( 1v,un1 \le v, u \le n ) — the description of an edge.

The given edges form a tree. The sum of nn over all testcases doesn't exceed 21052 \cdot 10^5 .

输出格式

For each testcase print a single integer — the maximum possible cost of the tree.

输入输出样例

  • 输入#1

    4
    4
    1 2
    2 3
    3 4
    5
    1 2
    1 3
    1 4
    1 5
    3
    1 3
    3 2
    7
    3 2
    2 5
    7 5
    3 1
    1 6
    1 4

    输出#1

    4
    1
    3
    3
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