Problem Statement: Sibling Nodes

You are provided with a Binary Tree consisting of 'N' nodes, where each node holds an integer value. Your objective is to identify and list all nodes that do not possess a sibling.

Note:

1. A node ‘U’ is defined as a sibling of node ‘V’ if both nodes share the same parent.
2. The root node is considered a sibling node.

Input:

The first input line contains an integer 'T', indicating the number of test cases or queries.

Each test case comprises a single line of space-separated integers representing the Binary Tree in level order. Each value corresponds to a node, and '-1' represents a null node.

Output:

For each test case, output a single line containing the values of all nodes without siblings, sorted in ascending order.
The output for each test case should appear on a new line.

Example:

Input:

1
1 3 8 5 2 7 -1 -1 -1 -1 -1

Output:

7

Constraints:

• 1 <= T <= 5
• 0 <= N <= 3000
• 0 <= node data <= 10⁹

Where 'T' is the number of test cases and 'N' is the number of nodes in the tree.

Time limit: 1 second.

Note:

You are not required to handle printing the output; this is managed for you. Implement the function to achieve the desired outputs.