These are actually quite difficult puzzles in the sense that they are very different from what you have seen in school. The solutions can be found by considering new perspectives of what is asked for.

Do make use of the hints. Solving these difficult problems with hints is still a great achievement!

If you don't know how to do them, try to understand the solutions. That may also not be easy, but our ambition with distributing these puzzles is to introduce you to new concepts. Once you read the solutions you learned something and you will be prepared for solving such problems in the future.

Orange puzzle ("Can't have it all") Hints Solution Overview/more examples Review paper

Blue puzzle ("Black & white circle") Hints Solution Extensions Hints to Extensions Solutions to Extensions

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