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Comment by motohagiography | Hacker News Reader

Was this the expected answer to the coding interview question at places like Renaissance Technologies, Jane Street Capital, and Galois?

This is really funny. I had an intuition there must be a lambda function solution for fizzbuzz, but I don't do coding interviews and never pursued it. I can see why now, because it's waaay out of my skillset, but so neat to read.

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The lambda's purpose here is only to turn it into a one-liner. It can be rewritten as

    def fizzbuzz(n):
        num_map = { 1: n, 6: "Fizz", 10: "Buzz", 0: "FizzBuzz" }
        return num_map[n**4%15]


    for i in range(100):
        print(fizzbuzz(i + 1))

The real skill would be to demonstrate that you know/remember/can apply Euler's totient theorem off-the-cuff in an interview!

We can even easily write it as a one-line without lambda:

    [{ 1: n, 6: "Fizz", 10: "Buzz", 0: "FizzBuzz" }[n**4%15] for n in range(1, 101)]

The lambda in the original code is just used to convert the 0..99 that's generated by range(100) to 1..100. Using range(1, 101) instead generates the appropriate range of numbers from the beginning.

I don't know about Jane Street or Galois, but Renaissance is full of mathematicians so I doubt they'd be impressed by Euler's theorem. Math students learn it in undergrad, it is considered basic.

Yeah if I get asked fizzbuzz at an interview I'll really think less of the interviewer and will try to propose a solution like that ;)

Jane Street maybe. I've not heard of Galois having a tricky interview process. From what I've heard of Renaissance, this would be insultingly trivial to ask.

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