What is the song that goes la la la la la la la la la la la la la la?

i heard it in a club last night but i couldnt make out the lyrics, all
i could make out at the chorus was "laaaaa la la la la, la la la la la
la la la laaa" and then it was like something something four/floor
it also had a rap. but the rap was only some parts like the beginning
and a part before the last chorus.