adnan's a fibber

fibber.rb

@fibs = {
    0 => 0,
    1 => 1,
}

def fib(n)
  cached_result = @fibs[n]
  return cached_result if cached_result

  new_result = fib(n-1) + fib(n-2)
  @fibs[n] = new_result

  new_result
end

fib(100)
@fibs.values.each { |n| puts n }

def fib(n)
  result = [0, 1]
  (3..n).each do
    result << result[-1] + result[-2]
  end
  result.first(n)
end

clever, but why result.first(n) and not just result?

@Kallin first(n) because if n = 0 or n = 1 you don't want to just return result = [0,1] because that's the first two numbers