Brain teaser circular jail

#1

I am not able to understand the explanation.

#2

Hey @mishikasrvastava
pls watch the video once again

as the door will be closed if that door no. has even no. of divisors
like 24
the divisors are: 1 ,2, 3 ,4, 6, 8, 12, 24

so the door: open close op cl op cl op cl

so the door will remain open if that door no. has odd no. of divisors
it will be posiible only in perfect squares

like 25 : 1 5 25

this is becoz for the perfect sq. no.
there will be one no. that is same, like for 25 we have 5*5
so it will generate only one no.

hope this will help u

#3

thanks for your help