foreach my $k (@k) {
  $s =~ m/(.)$k(.)/ ;
  if (($1 ne "\0") || ($2 ne "\0")) { delete $h{$k} ; } ;
}

[download]

You shouldn't use the variables $1 and $2 unless the match was successful because they retain their previous value if the match failed and so after the first successful match every key will be deleted. 

for my $k ( @k ) {
    if ( $s =~ /\0$k\0/ ) {
        delete $h{ $k };
        }
    }

[download]

In reply to Re^2: hash substrings by jwkrahn
in thread hash substrings by perlcat

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