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#9607. Proficient

統計

Given a tree of size $n$ and $m$ simple paths on the tree, you need to assign a color $c_i$ to each path such that no two paths of the same color share any common vertices.

Find the minimum number of colors required and construct a valid assignment.

Input

This problem contains multiple test cases.

The first line of the input contains an integer $c$, representing the subtask number. $c=0$ indicates that the test case is a sample.

The second line of the input contains an integer $t$, representing the number of test cases.

For each test case:

The first line contains two positive integers $n, m$.

The next $n-1$ lines each contain two positive integers $u_i, v_i$, representing the $i$-th edge of the tree as $(u_i, v_i)$.

The next $m$ lines each contain two positive integers $a_i, b_i$, representing the $i$-th path as the simple path from $a_i$ to $b_i$.

Output

For each test case:

The first line contains a positive integer $k$, representing the minimum number of colors required.

The second line contains $m$ positive integers, where the $i$-th number is the color $c_i$ of the $i$-th path. You must ensure $1 \le c_i \le k$.

If your output $k$ is correct and the sequence $c_i$ follows the format but does not satisfy the problem requirements, you will receive $15\%$ of the points for that test case.

Examples

Input 1

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

Output 1

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

Constraints

For all data, $1 \le t \le 10^5, 1 \le n, m, \sum n, \sum m \le 5 \times 10^5, 1 \le u_i, v_i, a_i, b_i \le n$.

  • Subtask 1 (3 pts): $n, m \le 5$.
  • Subtask 2 (14 pts): $m \le 5$.
  • Subtask 3 (9 pts): $\forall 1 \le i < n, u_i = i, v_i = i+1$.
  • Subtask 4 (20 pts): $n, m \le 1000, \sum n, \sum m \le 5000$.
  • Subtask 5 (22 pts): $\sum n, \sum m \le 10^5$.
  • Subtask 6 (32 pts): No special constraints.

Editorials

IDTypeStatusTitlePosted ByLast UpdatedActions
EditorialOpen Official EditorialQingyu- Download

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