Hey there

In many exams it is recommended by authorities to have same look as in photo so that no confusion would be there. But they also understand that 100% match is not possible so any changes which is not going to affect your look much will be accepted but you should not do anything which completely change your looks that may create problems for yourself.

Good luck

Hello,

No, there isn't any such thing.It is not mandatory to have a similar haircut when you appear in the entrance exam.If you need to carry passport size photo on the day of examination then you need to carry the same photo as it in admit card.You not to worry as long as things are taken care of.