Coin Change - VR Mock Coding Interview - #3

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Daniel Habib
·

2 min read

Check out this VR Mock Interview that goes over a “Coin Change” programming interview question. Video linked here & verdict/notes below!

Verdict

Pass!

The candidate passed this interview because of their ability to work through the problem, and even though their were hiccups throughout, there wasn't anything that would sink the interview. This candidate passed with a 4/5

Ratings

Coding: 3 Communication: 4 Problem Solving: 4 Inspection: 4 Review: 3

What they did well

  • Wrote out the input, output and example
  • asked intelligent questions
  • Thinking Greedy to start, challenges his own thinking and gets to the crux of the problem
  • identified the greedy approach, and challenged his assumptions and showed that he couldn't prove it
  • Feels like a conversation,
  • Very good communicator
  • Knew every individual coin was a base case
  • Writes great psuedo code
  • Great inspection, Good strategy, coding section
  • Index selection optimization
  • Caught his mistake and added 1 after being prodded

What could be better

  • diagram isn’t clear how he is progressing through the problem
  • started to fall apart when pushed on the runtime
  • Realized the history of the coins didn’t matter after being prodded
  • Got a little lost when he was strategized the coin change solution. Tied up in managing the index
  • Didn’t know to reference the call stack when asked about top down vs bottom up
  • Kept switching between top down and bottom up without bringing the interviewer along
  • Psuedo code , didn’t really have time to code
  • No need to do binary search on the coin, a premature optimzation
  • First iteration of code wasn’t functional
  • Had issues defining the output runtime never asked about the size of the coins
  • Didn’t review his code too thoroughly

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