Hi I am creating a vending machine application that takes coins. It takes 5p, 10p 20p 50p £1 and £2 coins. Now I need to keep track of all the coins when inserted e.g. if I insert 2 pounds in 5p coins. When I chose to refund the money I need the machine to refund all the coins in random denominations but to the amount of £2. Or if I do buy something for say 25p, I need the machine to refund the change again in random denominations but to the correct change.