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my $string = '---LL--C----LCSH-------CSHL-------LCSLH-------LCCHLSHCL-
+---';

# I want to loop through these strings and
# find maximal sets of two or more of the capital letters
# that do not begin or end with L
while ($string =~ /([CSH][CSHL]*[CSH])/g) {
    print "$1, ";
}

__OUTPUT__
CSH, CSH, CSLH, CCHLSHC,
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