Ruby Fundamentals IV: Non-core Change Machine Kata

kata_change_machine.rb

# Ruby Fundamentals IV:  Non-core Change Machine Kata

def is_valid_currency?(amount)
  amount.to_s.match(/\A\d+[.]{0,1}\d{0,2}\z/)
end

amount_due = rand(0.0..100.0)

puts "Amount Due: #{sprintf("%.2f", amount_due)}\n\nWhat did customer supply?"
amount_tendered = gets.chomp.to_f
# test if amount_tendered is valid


change_due = amount_tendered - amount_due
change_due_integer = (change_due*100).to_i
currency_due = {}
currency_due[:dollars]  = change_due_integer / 100
currency_due[:quarters] = change_due_integer % 100 / 25
currency_due[:dimes]    = change_due_integer % 100 % 25 / 10
currency_due[:nickels]  = change_due_integer % 100 % 25 % 10 / 5
currency_due[:pennies]  = change_due_integer % 100 % 25 % 10 % 5

puts "\nThe change due is $#{sprintf("%.2f", change_due)}\nYou should issue:\n\n"
currency_due.each do |key, value|
  puts "#{value} #{key}\n" unless value == 0
end