How to add a line after every few lines in vim

Question

I wanted to add a line after every 3 lines in a file (having about 1000 lines) using vim editor. Can someone help me out? Thanks, Alisha

Accepted Answer

there is a vim-specific regular expression to do that

```
  :%s/.*
.*
.*
/\0/g
```

- %s is vim ex command to substitute in the whole file

- .*
 is a line including the end of line

- \0 is the entire matched expression

-  vim way to say add a new line (not 
 as one would expect)

Edit: if you want anything else than a new line, just put the text in front of the  (properly regex escaped, if it contains some regex characters)

Solution