Special two digit numbers in a Binary Search Tree

Given a Binary Search Tree, the task is to count the number of nodes which are having special two-digit numbers.
Note: Special two-digit numbers are those numbers that satisfy the condition that the sum of their digits added to the product of their digits equals the original number.
Prerequisite:Special Two Digit Number | Binary Search Tree |

Examples :  

Input:

👁 Special-two-digit-numbers-in-a-Binary-Search-Tree

Output: 2
Explanation: The two special two-digit numbers in the input are 19 and 99. These numbers satisfy the condition of special two-digit numbers. Hence, the output is 2.

Input:

👁 Special-two-digit-numbers-in-a-Binary-Search-Tree-2

Output: 0
Explanation: There are no special two-digit number in the given input.

Approach:

The idea is to iterate through each node of tree recursively with a variable count, and check each node's data for a special two-digit number. If it is then increment the variable count. In the end, return count.

Below is the implementation of the above approach:

2

Time Complexity: O(n), thatn is the number of nodes in Tree.
Auxiliary Space: O(h), where h is the height of the tree and this extra space is used due to the recursion call stack.