This Brilliant Riddle would test your brain power.
There are 100 lights in a huge room. A switch panel outside the room has 100 switches each corresponding to one light in the room.
But none of the switches or lights are labelled, so it's extremely difficult to identify which switch turns on which light.
You are standing outside of the room... and your task is to map each switch to its corresponding light using a marker pen.
You have to do this mapping in minimum number of trips to the room.
Initially, all the switches are turned off.
What's the minimum number of times you need to enter the room to complete the mapping of each switch to its corresponding light.

Please note a few points:
(To check the state of a light, you must enter the room, you cannot check it from outside.)
(There is nothing related to heating of a light... everything here is perfectly logical)
So.
Pause the video..... and think logically.

and here is a hint for you.
(Hint : Surprisingly, the answer is a smaller number)

This video explains this puzzle the best way. You will certainly learn the optimal way and the best approach of solving difficult puzzles.
Of course it's a difficult riddle, but I encourage you to take your own time and try to solve this challenging riddle.
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