Have met them loads of times
One girl I use to run into a few time never acknowledged anytime just walked by as if I did not exist.
An other use to wave over to me and we went for a coffee once.
An other I met at a garage smiled at me and when I smiled at her and said hello, she came over and we walked and chatted for about 15 mins.
An other brought me out for dinner once
So it depends on the girl and I would leave it up to her to make a move if she wants to talk