InterviewBit Problems   Invert the Binary Tree : Unsolved

About the Invert the Binary Tree : Unsolved category (1)
Simple And Easy Soln In Java Using Recursion (1)
What' wrong with this approach? why dosen't it work? (2)
Well, We all know this is the scariest thing in the universe (4)
Best visual Hint/depiction of the problem! (1)
Simplest c++ solution Approach (1)
What is wrong with my approach? (2)
Question is not specific: what is "invert" is not explained (3)
Javascript will not complete solution in time (2)
Titles are hard to choose (1)