The following will match two words in a row: 
use strict;
use warnings;

my @strings = qw(
    /help/one/one/one/something_here
    /buy/cash/buy/water/water/water/nothing_here     
);

for (@strings) {
    if (m{\b(\w+)/\1\b}) {
        print "Dup is '$1'\n";
    }
}

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In reply to Re: Regex expression to match... by wind
in thread Regex expression to match... by Anonymous Monk

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