fibonacci closest numbers

fibonacci.rb

require 'net/http'
require 'json'

KUESKI_TOKEN = 'fbxfDZRWCxmdhxHfM-Q'

fibonacci_sequence = []

def fibonacci(x, cache = {})
  return x if x <= 1
  cache[x] ||= fibonacci(x-1, cache) + fibonacci(x-2, cache)
end

1.upto(100) do |x|
  fibonacci_sequence << fibonacci(x)
end

uri_get_input = URI('https://kueski.com/candidates/get_input')
res_get_input = Net::HTTP.post_form(uri_get_input, token: KUESKI_TOKEN)
api_input = JSON.parse(res_get_input.body)["value"]

puts "You received #{api_input}"

first_range = fibonacci_sequence.select{|item| item < api_input.to_i}.max
last_range = fibonacci_sequence[fibonacci_sequence.index(first_range)+1]

solution = api_input == last_range ? last_range : "#{first_range}-#{last_range}"

puts "The solution is #{solution}"

uri_send_solution = URI('https://kueski.com/candidates/send_solution')
res_send_solution = Net::HTTP.post_form(uri_send_solution, { token: KUESKI_TOKEN, solution: solution})
puts res_send_solution.body