I want to complete a time stamp in an R dataframe. The current timestamp is missing seconds, hh:mm, but it needs to be hh:mm:ss. In this case I just need to add ":00" to all the timestamps.

Timestamps looks like this `"10:25" "10:29" "11:32"`

But it needs to be `"10:25:00" "10:29:00" "11:32:00"`

I have tried the following, but nothing is being added.

```
gsub("(:dd)$","\\1:00",test$`TIME`)
gsub(" .*$", "\\1",test$`TIME`)
gsub("dd$", ":00",test$`TIME`)

```

Thanks