Special Binary Tree Problem Statement

Determine whether an arbitrary binary tree is special. A binary tree is called special if every node in this tree has either zero or two children.

Example:

Input:

3
5 1
6 2 0 8
-1 -1 7 4 -1 -1 -1 -1
-1 -1 -1 -1

Output:

true

Explanation:

Consider the binary tree:

Level 1: The root node of the tree is 3

Level 2: Left child of 3 = 5, Right child of 3 = 1

Level 3: Left child of 5 = 6, Right child of 5 = 2, Left child of 1 = 0, Right child of 1 = 8

Level 4: Left child of 6 = null (-1), Right child of 6 = null (-1), Left child of 2 = 7, Right child of 2 = 4, Left child of 0 = null (-1), Right child of 0 = null (-1), Left child of 8 = null (-1), Right child of 8 = null (-1)

Level 5: Left child of 7 = null (-1), Right child of 7 = null (-1), Left child of 4 = null (-1), Right child of 4 = null (-1)

Input:

The first line contains an integer ‘T’ denoting the number of test cases. For each test case, provide the binary tree's node values in level order (use -1 for NULL nodes).

Output:

For each test case, print either “true” if the tree is special or “false” otherwise. Each result should be on a new line.

Constraints:

• 1 <= T <= 5
• 1 <= N <= 10 ^ 3
• 0 <= DATA <= 10 ^ 9

Note:

• A binary tree is a tree in which each node can have at most two children.
• The given tree will always be non-empty with at least one node.
• Multiple nodes can have the same value, all node values are positive.
• No code for input/output interactions is needed; focus on implementing the logic for checking if the tree is special.