Round 1:

Some OS concepts were asked and one DS question was asked.

1.  Serialize and Deserialize a binary tree (not complete binary tree).

I did'nt use the infix and postfix approach and used queue, but had to make a lot of changes later to
handle the different use cases.

Round 2:

1 .   Check if binary representation(32 bit) of a number follows regex 1*0*.

Question is straight forward, interview gave a hint before that this can be solved using bitwise operator.

I was not able to come up with a direct approach so he moved on to the second question. Can this directly be solved using an any bitwise operator?