URL Replace / URL Rewrite

RouterOS Scripting
1

Hello,

I want to replace a sting in URL.

URL syntax:
http://IP:Port/URL

Source URL:
http://8.8.4.4:8080/index.php?action=post;topic=95749

After replace:
http://8.8.4.4:8080/index.php?action=post;topic=77777

How can I replace 95749 with 77777?

2

Can we do it?
Replacing string in a URL.