Find Nodes at Distance K in a Binary Tree

Your task is to find all nodes that are exactly a distance K from a given node in an arbitrary binary tree. The distance is defined as the number of edges between nodes.

Input:

The first line contains an integer T, the number of test cases. For each test case: 1. The tree's nodes are given in level order (use -1 for a NULL node). 2. The value of the target node is specified. 3. An integer K represents the required distance from the target node.

Output:

For each test case, output a list of node values that are exactly K edges away from the given target node. If no such nodes exist, return an empty list.

Example:

Input:
1
3 5 1 6 2 0 8 -1 -1 7 4 -1 -1 -1 -1 -1 -1 -1 -1
target = 5
K = 2

Output:
[7, 4, 0, 8]

Constraints:

• 1 ≤ T ≤ 100
• 1 ≤ N ≤ 3000
• 0 ≤ K ≤ 3000
• 0 ≤ nodeValue ≤ 3000

Note:

- The binary tree is non-empty and can contain nodes with the same value. - If there are multiple nodes fulfilling the distance requirement, their order in the output list does not matter.