The answer to life, universe, everything

I'm asking this question on behalf of a good friend. This question has been plaguing him I guess for about 2 years and 4 months already. He has been actively seeking for an answer but has been unsucessful for various reasons. It is just simply, what does a girl you know for about 3-4 days only mean when she hugs you before she gets off the MRT train for home?
Sure brings back old memories...