gghelpneeded:

As the Anonymous Monk mentioned, in your code. Different sources of data may have different quirks, so you need to know about your data source to figure out the best way to clean up the data. You want to be careful with your fixes, though, to make sure you make the appropriate conversions.

For example, in some accounting reports, parenthesis around a number may indicate that it's negative value rather than positive. Other systems may include commas, currency symbols or other formatting information. Yet other systems use a trailing sign on the data. Once you find out all the quirks, you shouldn't have too much trouble writing an appropriate subroutine to clean up and convert the data to the form you need.

...roboticus

When your only tool is a hammer, all problems look like your thumb.

In the code itself, see example below:

#!/usr/bin/perl -l

# http://perlmonks.org/?node_id=1137878

use strict;
use warnings;
$| = 1;

while(<DATA>)
  {
  my @value = split;

  tr/()//d for @value; # THE FIX

  print $value[1] - $value[0];
  }

__DATA__
(15) 20
(3) 50
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