day1.rb

def fuel_required(mass)
  fuel = (mass/3).to_i - 2
  if fuel > 0
    fuel + fuel_required(fuel)
  else
    0
  end
end

# p "Fuel for 1969 = #{fuel_required(1969)}"
# p "Fuel for 100756 = #{fuel_required(100756)}"

sum = 0
DATA.each_line do |line|
  module_mass = line.to_i
  sum += fuel_required(module_mass)
end

print "Total fuel required:\n#{sum}\n\n"

__END__
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