During a weekend interview, it seemed like people just wanted to show themselves as smarter, and weren't concerned about my approach or eligibility. When I answered all four questions as listed below, the interviewer truly looked devastated. From then on, he started reacting as if I were dumb. For instance, after listening to my answer to one question (which he completely misunderstood), he asked me to write a program for it. He again didn't understand it and replied he was looking for class design and a modular approach.

Anyway, after that, he started asking questions to design and implement Google Maps and other APIs. He was a completely irrelevant guy and looked like he never knew what the interview process means. Is it to get a valuable resource or to show off?

1. Mirror a given binary tree
2. Check if a given binary tree is BST
3. Right view of a binary tree
4. Lowest common ancestor of two nodes in a binary tree

-- After all these answers, he got mischievous and started acting like a moron -- :-)

1. Reverse k nodes from the beginning and end of a linked list. For example, if the list is 1 2 3 4 5 6 7 8 9 and k=3, the result should be 3 2 1 4 5 6 9 8 7.

When I answered this, he got completely frustrated. The suggested approach was to get two lists (e.g., 1 2 3 and 7 8 9), reverse them, and then reconnect them by pointing the end of the first list to the head of the reversed second list, and the end of the reversed first list to the node following the first reversed segment.

Of course, this requires some amount of code to handle edge cases, which makes it complex. This part he never understood, even when I proved it by dry-running all cases.

1. Design and implement a Google Maps API.