Count Leaf Nodes in a Binary Tree

Given a binary tree, your task is to count and return the number of leaf nodes present in it.

A binary tree is a data structure where each node has at most two children, referred to as the left child and the right child. A leaf node is a node with both left and right child nodes as NULL.

Input:

The first line contains an integer 'T', representing the number of test cases. For each test case, you are given the elements of the binary tree in level order format. Each value of a node is separated by a space on a single line. Use -1 to represent a NULL node.

Output:

For each test case, return the count of leaf nodes in the binary tree.

Example:

Input:

1
20 10 35 5 15 30 42 -1 13 -1 -1 -1 -1 -1 -1 -1

Output:

4

Explanation:

The tree formed by the example input is:
Level 1:    20
Level 2:   /   \
         10    35
Level 3:  / \   / \
        5  15 30 42
Level 4:   /    |   |
         13   (null)
Leaf nodes: 5, 30, 42, 13

Constraints:

• 1 ≤ T ≤ 100
• 1 ≤ N ≤ 10^3, where N is the number of nodes in the tree
• 1 ≤ data ≤ 10^9
• Time Limit: 1 sec

Note:

Input format is intended to provide clarity on how the binary tree is represented. The sequence will be given in a single line separated by spaces. You only need to implement the function to calculate the leaf nodes, printing will be handled elsewhere.