The first round was a coding round, which was pretty much like any other coding round with easy to medium difficulty level questions.

Next, there were two technical phone interviews. The interviewers were friendly, and there was nothing to worry about. Just hope that you don't get a Chinese interviewer with a strong accent, as it's difficult to communicate effectively.

Questions are posted below.

Sum of leaf nodes of a binary tree without using recursion or stack space.

(Constant space solution)

Some game which can be solved by BFS/DFS traversal.