#!/usr/bin/env ruby

def calculate_fuel(mass)
  return (mass / 3).floor - 2
end

def calculate_fuel_with_fuels_fuel(mass)
  fuel_required = calculate_fuel(mass)
  if calculate_fuel(fuel_required) > 0
    fuel_required += calculate_fuel_with_fuels_fuel(fuel_required)
  end
  return fuel_required
end

fuel_requirements = 0

ARGF.each do |line|
  mass = line.to_i
  fuel_requirements += calculate_fuel_with_fuels_fuel(mass)
end

puts "Fuel Requirements: #{fuel_requirements}"