A funny one-button game where you have to trick an arcade cab into giving you credits

Author Comments:

A short and funny one-button game where you have to "buy" as many credits as possible from an arcade cabinet using a single coin tied to a string.
Do you know how to get unlimited credits with a single coin?
- Tie a coin to a string.
- Insert the coin inside the machine to buy a credit.
- Then click your mouse button repeatedly to pull the string, until you get your coin back!
- Send the coin back into the machine, buy another credit, and pull it out again.
- Repeat over and over!
Sound simple right?
Unfortunately, modern arcade cabinets are protected against such techniques; they will send out a lot of flying red stuffs that will cut your string if you don't avoid them. So you'll have to pull the string wisely to avoid them.
How many credits can you buy?
This game is also freely available on Android:
https://play.google.com/store/apps/details?id=air.com.ludoscience.InsertCoin
----------- UPDATE -----------
I've just corrected a bug preventing you from obtaining the third medal. Sorry for the inconvenience, and thanks to all of you who reported the bug to me!