my $terminator = $/;
undef $/;
$mult = <MULT>;
$/ = $terminator;

{  # Begin localization block
   local($/);
  $mult = <MULT>;
} # End localization block

A123456 ,789,543,MoreData
A654320 ,789,543,MoreData
A024689 ,789,543,MoreData

A123456
A654321
A024689
A987654

#!/usr/bin/perl

use strict;
use warnings;

my $total;
my $multfile;
my %multhash;

my @Atmp;                  # for debugging & education purposes

open($multfile, "<", "mult.txt") or die("Can't find list of multiplicative sequences in mult.txt");
while (<$multfile>) {
  chomp;
  next if /^$/;            # skip blank lines
  $multhash{ $_ } = $_;    # add to hash, using element as the key & data
}
close($multfile);

@Atmp = (keys %multhash);  # for debugging & education purposes
print "@Atmp\n";           # for debugging & education purposes

$total = 0;
while(<>) {
  if (m/(A\d\d\d\d\d\d) ,((-?\d+,)*-?\d+),/) {
    if (exists $multhash{ $1 }) {
      print "go(\"$1\", [$2]);\n";
      $total++;
    }
  } else {
    print "print(\"Error reading line: $_\");\n";
  }
}
print "Total=$total\n";

#!/usr/bin/perl

use strict;
use warnings;

my $total;
my $multfile;
my %multhash;

open($multfile, "<", "mult.txt") or die("Can't find list of multiplicative sequences in mult.txt");
while (<$multfile>) {
  chomp;
  next if /^$/;            # skip blank lines
  $multhash{ $_ } = $_;    # add to hash, using element as the key & data
}
close($multfile);

$total = 0;
while(<>) {
  if (m/(A\d\d\d\d\d\d) ,((-?\d+,)*-?\d+),/ && exists $multhash{ $1 }) {
    print "go(\"$1\", [$2]);\n";
    $total++;
  }
}
print "Total=$total\n";

#!/usr/bin/perl

use strict;
use warnings;

my $multfile;
my %multhash;

open($multfile, "<", "mult.txt") or die("Can't find list of multiplicative sequences in mult.txt");
while (<$multfile>) {
  chomp;
  next if /^$/;            # skip blank lines
  $multhash{ $_ } = $_;    # add to hash, using element as the key & data
}
close($multfile);

while(<>) {
  m/(A\d{6}) ,(\d+,\d+)/;
  print "go(\"$1\", [$2]);\n" if exists $multhash{ $1 }
}