# save test number to .Rdata file
count_test <- function(){
  if (!file.exists("counter.Rdata")){
    counter <- 1
  save(counter,file="counter.Rdata")}
  if (file.exists("counter.Rdata")){ load(file="counter.Rdata")
    counter <- counter + 1
  save(counter, file="counter.Rdata")}
  return(counter)
  }
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.