The last Monday, I was on an interview where I was asked to solve this puzzle "Three Light Bulbs & Switches in a Room" http://puzzles.nigelcoldwell.co.uk/seven.htm

#Hint - I did not get that job.

#Confession: I never was good with all these #puzzles, #brainteasers and #crosswords. Ditto about #Chess. But somehow, between 1972 and 2016, I graduated University with Major Applied Math and now continue working as a Software Developer and Data Analyst.