How to generate random vector with whole numbers and defined length in R?

I've heard about

hereset.seed(12)
runif(12) 

But I need Whole random numbers in my vector, for example, with vector length 5.

Like:x<-c(rand,5) (i know it's fake command, just for idea) to get c = 9,0,4,3,5

And also I would like to know how to get such vector only with number range between 15 and 34.

Thanks!