Notes

Whiteboarding Tips and Tricks

• Companies whiteboard because steps for solving wb problems are almost nearly identical to solving real-world practical situations.
  • They are looking to test a few things:
    • Can you think algorithmically? Think efficiently?
    • Are you a good communicator?
    • Can you code neatly and correctly?

Correct Steps

1. Repeat and clarify the problem.
2. Identify Edge Cases & I/O.
3. Pseudocode IF NECESSARY.
4. Implement Code.
5. Walk through an example input.
6. Det. Time and Space (Theta).
   • Time is expensive, space is cheap.
   • Ask interviewer is optimization is even necessary.

Strategies

• Hash Maps.
• Divide and Conquer DP Programming.
• Using Math Properties.
• Amortized Analysis : Method for analyzing a given algorithm’s complexity, or how much a resource, especially time or or memory, it takes to execute.
• Keeping a Stack or Queue on the side to track values.
• Keep two pointers for the same iteration.
• Perform an operation twice.
• Sort the input.
• Approach the problem from the other end.
• Use binary numbers instead of decimal numbers.
• Use binary search instead of incrementation.

If you have seen the problem before, just tell them you have.