Agree with all the advice above. I walk my girl in a small park in New York City for most of her walks and we face other dogs, off leash dogs, kids on bikes, kids on scooters, groups who think it is fine to walk 5 across and block the entire sidewalk, etc. I walk my girl on my inside so that she is safe so we do the switch from left to right depending on direction. I also always have treats. When in doubt, I stop well before the dog/people in question (whenever possible) and treat my girl while letting them pass.
This is not to say that my girl isn't friendly and that 90% of the dogs we meet in the park on a daily basis aren't friendly, just that I would rather have her safe and controlled.