Puzzle

Hi all, if you have a spare time you may think about this puzzle:

there is a light in a room.
you're outside, and you have 3 switches, one of them turns the light on and off,
the others do nothing. sure you can't know if the light is on or off unless you enter in, so you cannot know from outside.
initially the light is off.
you can enter the room only once.

how can you know the switch that controls the light ??

hani wrote:

Hi all, if you have a spare time you may think about this puzzle:

there is a light in a room.
you're outside, and you have 3 switches, one of them turns the light on and off,
the others do nothing. sure you can't know if the light is on or off unless you enter in, so you cannot know from outside.
initially the light is off.
you can enter the room only once.

how can you know the switch that controls the light ??

betdwi Interrupteur numéro 1 chi 3 min, bterja3 btetfi.
w btedwi interrrupteur numéro 2.
w betfout

iza kenet el lamba medwiyeh donc interupteur 2
else
iza kenet el lamba berdeh .... interupteur 1
else
interrupteur 3
iza

awiyyeh, that's right !

kbir wael hehe

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