Hi, I've got the following code: p <- 0.34 pb <- p*100 pr <- (1-p)*100 A <- rep(0,pb) # a vector with 34 "zeros" B <- rep(1,pr) # a vector with 66 "ones" Now if I type length(A), R answer correctly 34 but if I type length(B), R answer 65 instead of 66. I don't understand why it happens. Can anyone help me? Thanks in advance. Paolo