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Random logic puzzles and brain teasers. Fun to do and useful for many job interviews!
How to get correct advice when you can only ask one question from either a liar or a truth-teller (when you don't know who is what)
Separating the truthteller from the togglers!
Saving Earth from becoming a mushroom farm.
What happens when 100 perfect logicians have to figure out if they each have a blue forehead?
Do not watch before Blue Forehead Room. THIS IS THE SOLUTION!
The perfect logicians are at it again.
Turning light bulbs on and off.
Counting paths in a square
Extending the path counting to three dimensions