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Random logic puzzles and brain teasers. Fun to do and useful for many job interviews!
Deductive reasoning problem from Singapore.
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