change_machine.rb

def dollar_due(change_due)
  d_due = (change_due / 1.00).to_i
  puts "#{d_due} dollars"

  left_overs = (change_due % 1.00).round(2) 
  if left_overs > 0.25
    quarter_due(left_overs)
  elsif left_overs > 0.10
    dimes_due(left_overs)
  elsif left_overs > 0.05 
    nickels_due(left_overs)
  else
    pennies_due(left_overs) 
  end
end

def quarter_due(change_due)
  q_due = (change_due / 0.25).to_i
  puts "#{q_due} quarters"

  left_overs = (change_due % 0.25).round(2) 
  if left_overs > 0.10
    dimes_due(left_overs)
  elsif left_overs > 0.05 
    nickels_due(left_overs)
  else
    pennies_due(left_overs) 
  end
end

def dimes_due(change_due) 
  d_due= (change_due / 0.10).to_i
  puts "#{d_due} dimes"

  left_overs = (change_due % 0.10).round(2) 
  if left_overs > 0.05
    nickels_due(left_overs) 
  else
    pennies_due(left_overs) 
  end
end

def nickels_due(change_due)
  n_due= (change_due / 0.05).to_i
  puts "#{n_due} nickles"

  left_overs = (change_due % 0.05).round(2) 
  pennies_due(left_overs) if (left_overs < 0.01)
end

def pennies_due(change_due)
  p_due= (change_due / 0.01).to_i
  puts "#{p_due} pennies"
end

amount_due = 13.26
puts "Amount Due: #{amount_due}"
puts "What did customer supply?"
print "> "
tendered = gets.chomp.to_f

change_due = (tendered - amount_due).round(2)
puts "If the customer pays $#{tendered}, the total change due is $#{change_due}."
puts "You should issue:"

if change_due >=1.00
  dollar_due(change_due)
elsif change_due >= 0.25  
  quarter_due(change_due)
elsif change_due > 0.25
  dimes_due(q_due)
elsif change_due > 0.10
  nickels_due(change_due)
else 
  pennies_due(change_due)
end