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1st Round:

Behavioral + longest consecutive sequence.

Can be solved with map in O(n) time.

2nd Round:

Question: Given an integer array, output all combinations of cell phone texting letters with the given numbers.
DFS solves the problem. So does BFS.

Follow-up: Check whether the given text matches with a given integer array.
Solution: Check whether the lengths match at the first traversal. Then reverse-map the text with the number.

3rd Round:

Question: Design a status post system that supports status store and search on statuses that has a string or multiple strings in them.

4th Round:

Question: LRU cache.
The whole whiteboard was filled by my codes….Afterwards the interviewer asked two questions about high level design.

5th Round:

Question: Behavioral + move zeros with minimum writes.
I went with index insertion but not sure if this gives minimum writes.