Do guys like it when girls smile at them?

Sometimes I like to smile at people, especially guys, since usually I don't have the guts to go up and talk to them. But I don't know why sometimes they just look at me, and don't smile back very often. My friend and I were talking about this and she said this always happens to her. My friend is really pretty, though, so do guys like it when girls smile at them? (not in a creepy, showing teeth way, but like just a small smile) :)
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+1 y
Oh by the way guys if this has happned to you where you didn't smile back, why didn't you?
Do guys like it when girls smile at them?
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