help with regular expression

[fgiorgio]

Hello
I would like to find aand replace exactly the number on each row.
For example
9 must be replaced by 500
59 must be replaced by 501
599 must be replaced by 800

Each number on the left is an exact phrase. This means that if I have 599, the first 2 lines MUST be skipped and it should just be replaced by 800.
What is the regular expression on SEARCH?

Hope it is clear my question
Thanks for your help

[DigitalVolcano]

to find the exact number you can use the \b word boundary identifier

so

Code: Select all

\b9\b

Will find 9 and not 599