Dear Monks,

I am trying to implement a scientific term extraction pattern in Perl however so far I am unsuccessful:

This is the pattern: 
((A|N)+|((A|N)*(NP)?)(A|N)*)N

[download]

It should return matches with sequences like: NNNN, NAAN, ANPN etc.

Partially it works. My Perl code looks like: 
my @can = ('NNAN', 'BPPAN','ANPN', 'NNAPN');        
foreach $value (@can) {
    if ( $value =~ m/^((A|N)+|((A|N)*(NP)?)(A|N)*)N/ ) { print "match:
+ $value\n"; }
}

[download]
However it shouldn't return a match with NNAPN since it should accept only NP sequence. How can I change it in order to work?

In reply to matching patterns by Anonymous Monk

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