You should be fine changing the root record. Whenever an email comes in it will always look at the MX records. There are two things to check though.

The MX records will point to a domain name, are they pointed at the root domain? Secondly do they use any form of webmail? You might need to create another record such as mail.example.com in order to ensure that they can still access these two things.

Most sender validation uses different DNS entries and doesn't rely on the A records in any way so you should be fine changing things.

How to set A Records and MX records correctly
As I see here there is a fast and short way to Convert vector to string separated with a character in c#:

var result = string.Join(";", data); 
var result = string.Join(";", data.Select(x =&gt; x.ToString()).ToArray()); 


I wan to know is there a same way in c++ to do this?
