InterviewBit Problems   2-Sum Binary Tree : Unsolved

About the 2-Sum Binary Tree : Unsolved category (1)
C++ easy soln using hashing (1)
Very easy solution using hashing c++ (1)
Error in testcases (2)
Working for sample test cases but not accepting can any one help me in this easy 5 lines of code (2)
Important! Must read, will help in this and future problems (2)
Easy to understand O(N) time and O(h) space Java code with proper naming and comments (1)
Easily done Using Map (1)
No match of custom input and code checker out (2)
Repititve Values (1)
Wrong test case for bst (4)
How to traverse these kind of values of a tree? (2)
There can be two approaches to solve the problem (2)
Custom input gives correct answer, but fails in the actual test (2)
Custom input give correct ans but same test case failed on submition. Test Case:9 17 2 18 -1 8 -1 -1 -1 -1 9 (2)
Code giving different answers for custom and test case.... what's wrong with the platform? (2)
Easiest solution using map (1)
Editorial Solution: Isn't it O(n) space as it's possible that the set contains all distinct n elements? (1)
Weak Test Cases :( (2)
Memory Limit is not cheking by online judge (2)
Organized Solution - Python 3 (1)
Different answer in Submit and Custom Test (2)
Same logic works in java, but not in c++ ? can anyone help (4)
Test and custom test on a same test case giving different answers (2)
Proposed java solutions doesn't meet given constraints (1)
Solution uses O(n) space (2)
BST or Binary tree (1)
Hint gives nothing, memory restriction met by "know-the-trick" solution only (1)
How to optimize space? (4)
I am not sure how the tree is built in the given problem here (1)