Cumulative sum for positive numbers only

Question

I have this vector :

x = c(1,1,1,1,1,0,1,0,0,0,1,1)

And I want to do a cumulative sum for the positive numbers only. I should have the fol

Answer 1

x<-c(1,1,1,1,1,0,1,0,0,0,1,1)

skumulowana<-function(x) {
  dl<-length(x)
  xx<-numeric(dl+1)
  for (i in 1:dl){
    ifelse (x[i]==0,xx[i+1]<-0,xx[i+1]<-xx[i]+x[i])
  }
wynik<<-xx[1:dl+1]
return (wynik)
}

skumulowana(x)
## [1] 1 2 3 4 5 0 1 0 0 0 1 2