Reorder Edges Problem Statement

Given a connected directed acyclic graph with 'N' nodes and 'N-1' edges, where each pair of nodes is connected by exactly one edge, you can perform the following operation any number of times:

1. Select two nodes 'X' and 'Y' having a direct edge between them.
2. Reverse the direction of the edge; if it is from 'X' to 'Y', change it to 'Y' to 'X', and vice versa.

Your objective is to reorder the edges such that there is a directed path from each node to node 0 with the minimum number of edge reversals.

Input:

The first line contains an integer 'T', the number of test cases.

Each test case starts with an integer 'N', the number of nodes in the graph.

Then follow 'N-1' lines, each containing two integers 'U' and 'V' indicating a direct edge from 'U' to 'V'.

Output:

For each test case, output the minimum number of operations needed to ensure a directed path exists from every node to node 0.

Example:

Input:

T = 1
N = 5
Edges: (0,1), (1,2), (3,2), (4,3)

Output:

2

Constraints:

• 1 <= T <= 5
• 1 <= N <= 3000
• 0 <= U, V <= N - 1
• Time Limit: 1 second

Note:

You do not need to print anything as the task is to implement the function which performs the operation.