Codeforces Round 875 (Div. 2)
C
Copil Copac Draws Trees
Codeforces
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原题
← BD →
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Copil Copac is given a list of $n-1$ edges describing a tree of $n$ vertices. He decides to draw it using the following algorithm:

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  • Step $0$: Draws the first vertex (vertex $1$). Go to step $1$.
  • Step $1$: For every edge in the input, in order: if the edge connects an already drawn vertex $u$ to an undrawn vertex $v$, he will draw the undrawn vertex $v$ and the edge. After checking every edge, go to step $2$.
  • Step $2$: If all the vertices are drawn, terminate the algorithm. Else, go to step $1$.
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The number of readings is defined as the number of times Copil Copac performs step $1$.

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Find the number of readings needed by Copil Copac to draw the tree.

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Input

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Each test contains multiple test cases. The first line of input contains a single integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases. The description of test cases follows.

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The first line of each test case contains a single integer $n$ ($2 \le n \le 2 \cdot 10^5$) — the number of vertices of the tree.

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The following $n - 1$ lines of each test case contain two integers $u_i$ and $v_i$ ($1 \le u_i, v_i \le n$, $u_i \neq v_i$) — indicating that $(u_i,v_i)$ is the $i$-th edge in the list. It is guaranteed that the given edges form a tree.

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It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.

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Output

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For each test case, output the number of readings Copil Copac needs to draw the tree.

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Note

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In the first test case:

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After the first reading, the tree will look like this:

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image

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After the second reading:

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image

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Therefore, Copil Copac needs $2$ readings to draw the tree.

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样例

Input #1
2
6
4 5
1 3
1 2
3 4
1 6
7
5 6
2 4
2 7
1 3
1 2
4 5
Output #1
2
3
InputCopy OutputCopy
题目信息
题号
1831C
时间限制
3 s
内存限制
256 MB

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。