I am new to Perl, I need some help. I have to create a regular expression like 


^K1_(\w*\d*)$|^ASC_(\w*\d*)$|^GEB_(\w*\d*)$|N1_(\w*\d*)$.

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In this expression, the user will provide the nodes(K1,ASC,GEB,N1 etc) in a .txt file.The nodes provided by the user may change,sometimes it can be 4 or 5 or 6 etc. After the regex is formed I have to compare it with a nodeVal and delete the respective nodes. The nodeVal is defined as follows 

$nodeVal =~ s/^\s+|\s+$//g; #remove leading and trailing whitespace
$nodeVal =~ tr/"//d; #remove quotation marks

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In reply to Dynamic Regular Expression by Pratikh

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