Kissing Coins

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Try to bring the coins as close to each other as possible, without overlaps.


The sum of all distances between (the rims of) any two coins is displayed at the left border. The goal is to minimize this score.

There are three given challenges. You can create your own challenges by changing the sizes of the coins with the "size" slider.


Contributed by: Karl Scherer (June 2015)
Open content licensed under CC BY-NC-SA



Click a coin and drag it as close as possible to another coin. Now move a third coin close to the first two, and so on.

You will find that a coin is repulsed the moment it overlaps with another coin. Two coins can only get as close as touching each other.


"challenge" popup menu: There are three challenges given. Challenges two and three use coins of different sizes.

"reset": Restore the starting position with "reset". There is also a counter so you can see how often you have clicked the reset button. So instead of asking who can solve the puzzle fastest, you can ask who uses the fewest resets.

"coin": Select a coin number to edit the coin's size.

"size" slider: This lets you set the size of each coin.

"minimize score": This shows the sum of all distances between the border lines of any two coins.

"target": If you manage to get below the target, you win.


Be careful with your approach, especially in the third challenge, where you can easily lose one or two coins from view.

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