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The following code solves your problem as specified.

If it does not do what you WANT, you need to improve your specification. 

perl -pe '$x++ ? s/\bvalues\b/100 for string_name100(Transition_11)/
               :  s/\bvalues\b/500 for string_name500(Transition_11)/
         '   FileName.lib > NewFileName.lib

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Of course, it would help if you showed us what you TRIED, and explain what you have trouble with.

Please read How do I post a question effectively?.

             When in doubt, mumble; when in trouble, delegate; when in charge, ponder. -- James H. Boren

In reply to Re: Parse a file, replace a particular strings and save new file by NetWallah
in thread Parse a file, replace a particular strings and save new file by waytoperl

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