The first-round interview was conducted very poorly. I was told this was supposed to be a "Technical Chat"; however, the goals of this were never explained. It seemed to be a coding challenge where they tested whether I knew archaic details about a programming language and peppered me with trick questions.

The interviewer was late and arrogant throughout the process. His communication skills were extremely poor as well. The interviewer refused to answer direct questions about the problem. Despite not specifying any requirements for the problem, he complained that I didn't focus on having an optimal solution at the beginning.

The interviewer was only experienced with Java/Kotlin-style programming and couldn't understand the C++ I was using. This also extended to the idioms of the languages (Java frequently uses helper methods to create temporary variables and return results; C++ generally leaves this to the caller).

It took three tries of him asking me what the depth of an arbitrary tree with n nodes is before he tried a question that could almost be answered (what's the best, worst, and average depth?). All of this was just to answer how much temporary data would be created by a recursive function with no local variables.

At the end, the interviewer stated that I didn't need to know everything about my programming language, and then immediately followed that up by saying that I should have known everything about my programming language. He seemed unhappy that I had to look up the syntax for stringstream during the interview, even though he stated that it's okay to look up syntax for things.

Red flags from the interview:

• Arrogance from the interviewer.
• Poor communication skills from the interviewer.
• The interviewer said he no longer works 10 hours a day; he only works 8 or 9.

Implement serialization/deserialization for a tree data structure.

Part 1: A binary tree.

Part 2: An n-ary tree.

I did not need to focus on the format of the serialized string or error handling.