Hi, i'm trying to resolve a regex problem. I'm trying to use a backreference but don't know how. My documentation says I should use \1(or \l?)for that. Information on the internet says it should be g1,g2 etc. But neither seems to work. I have an example. I developed this regex to print all 3-letter words:

$tekst = "hoii hoi and oi";
while($tekst=~/\b(\w\w\w)\b/g){
print "$1\n";
}

[download]

I want to change it into all 3-letter words that occur more than once. So something like:

/\b(\w\w\w)\b\g1/g)

[download]
Maybe someone can tell me the proper way to do this. Thank you in advance.

In reply to regex backreference by Anonymous Monk

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