Pair Sum in BST Problem Statement

Given a Binary Search Tree (BST) and a target value K, determine if there exist two unique elements in the BST such that their sum equals K.

Input:

An integer T, the number of test cases. For each test case, the first line contains the BST elements in level order format. Values of nodes are separated by a space. Use -1 for null nodes. The second line contains an integer K, the target sum.

Output:

For each test case, output 'true' if any pair of unique elements sums to K, otherwise output 'false'.

Example:

Input:

20 10 35 5 15 30 42 -1 13 -1 -1 -1 -1 -1 -1 -1
33

Output:

true

Constraints:

• 1 ≤ T ≤ 5
• 1 ≤ N ≤ 103
• 0 ≤ DATA ≤ 109
• 1 ≤ K ≤ 109

Where DATA represents the value of each node, and N is the number of nodes in the BST.

Time limit: 1 sec

Note:

No need to print the output; implement the function.