ObsidianJournal/Work/Edgar Munoz interview.md

#interview #logos #pair-programming

Ricardo sent him the Minesweeper problem.

Wasn't early to the meeting. Showed up at 13:02

Console application in C#, limited GUI

Seems familiar with Visual Studio. Able to explain his basic plan to get going: two models (Cell and Board), one service to calculated neighboring cells.

Interesting choice: adding "NeighborCount" on the cell model--should the cell model know about its neighbors?

IN progress: ahs not initialized the Board property yet--how will he discover this? Got NRE when he ran this. Easily found that he missed initializing the BoardGame property, explained why it threw well. Struggle a little to initialize the multi-dimensional array correctly.

Questions:

1. Can you GridSize everywhere to avoid errors?
2. Does each Cell really need to know it's neighbor mine count? Or is that something the board knows about?
3. Instead of a (Row, Column) comment, is there another way we could label the values?
4. Is there a way to calculate the coordinates of the surrounding cells without statically constructing a list of offset pairs?
5. You iterate through all cells in the board multiple times. Can you extract that logic to reuse wherever needed instead of copying it? Looking for an answer that includes passing a function to a method. His answer: method with flag to identify what to do in function.
6. Can he explain why using GridSize at the property initialization level doesn't work? He couldn't explain it--he needed a const or static integer for GridSize instead of a readonly class field. Opted to initialize the property at the top of the constructor. His answer: use it in the loops with the proper adjustments
7. Can he simplify the user input questions (like don't show option for placing a flag if no squares are revealed yet--ie, impossible to know where mine is yet), or does he want to allow a user to place flags without knowing
8. How can you communicate to the user better about what's going on (found mine or tried to place flag on revealed square, for example)? His answer: create another while block, while input is not valid, keep asking, showing message
9. What if someone enters a row or column that does not exist on the board?

Nits:

1. Property, field and variable naming not consistent
2. Not communicating to user if flag cannot be placed because cell is revealed
3. Unnecessary comments

Issues:

1. Reaching into the Board class to set cell properties directly in the BoardGame field instead of letting the Board class own manipulating the BoardGame
2. Mixed logic of revealing the cell with "SearchNeighbors" method logic
3. Somewhat spaghetti logic
4. Quite a few hard-coded numbers when they could be easily calculated

Notes:

1. Using Random to fill 10 mines into the board, knows basics of Random API.
2. Speaks English very well
3. Did not run the program early to see if there were errors
4. Found a bug he wrote in column and row check before executing program by thinking about it logically and visualizing the board.
5. Has a bug using .Length of a multi-dimensional array! Will be x * y and not x as he's hoping. He figured it out without any prompting from me and used GridSize in the check instead.
6. He had thoughts about the Board.BoardGame field--renaming it. This is a good sign to me, thinking about clearing naming something that's redundant (against the class name).
7. Used a Queue<T> to do a breadth-first search of neighboring cells.
8. Talked through logic of revealing 0-neighboring-mine-count cells well
9. Recognized duplicate logic of calculating neighboring cell coordinates and reused it
10. Decided to have property to keep track of number of revealed cells instead of recalculating number each time the user plays.

His thoughts on things to improve code?

• Valid input of users
• Fix revealing same cell twice
• Logic of checking if user won: should work, but not happy with it. Its highly dependent on logic of revealing cells. So it's fragile. Would prefer to more independent process where user won.
• Moving logic to BFS outside of class., thinking about single responsibility principle. Searching the board is task of the board, however.