How to use VIM replacement to use the hit part in the pattern string

Question

The description of the problem is rather obscure, so I will give an example directly. There is a file like this {code...}. I want it to be replaced by {code...}. How should I write it?

仅有的幸福 · Answer

vim’s regular expressions are quite special, see http://vimregex.com/, but it supports back references, but you need to use escaped brackets ( 和 )，然后在替换部分依序引用（如， 1).

:%s:A$\d\+$:FB:g

PHP中文网 · Answer

:%s/A(d+)/F1B/g
You can use regular expressions after escaping