fizzbuzz.rb

def solution(number)
  {
    15 => "FizzBuzz",
    5 => "Buzz",
    3 => "Fizz",
  }.select { number % _1 == 0 }.map { _2 }.first
end

raise unless solution(3) == "Fizz"
raise unless solution(5) == "Buzz"
raise unless solution(15) == "FizzBuzz"

puts "It works!"

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