How to change values ​​using find and replace?

Question

Regular Expressions

There is a file with markup, for example, 100000. The number of such repeated markups is more than 100+. How to make it so that every second element can be quickly replaced by 100500, for example?
Is there any regular expression for this?
Of the programs there is Sublime Text - but there Search and Replace works in such a way that it changes all the items at once.

Answer 1

Find 100000(.*?)100000
Replace with 100000\1100500
Perhaps, in some editors you need not \1, but $1, or lazy search does not work, or which checkboxes must be indicated (for multi-line, for example). Try different things and it will work.