You really, really need strictures - always use strictures (use strict; use warnings; - see The strictures, according to Seuss). A quick glance through your code shows the following issues, at least some of which would be highlighted by 'strict':

  1. use == for numeric compare, not eq ($type eq 2)
  2. What is the scope of @char?
  3. Where does $x get a value?
  4. Use three parameter open and lexical file handles.
  5. What is $a = () supposed to do?
  6. Use Perl for loops rather than C for loops.
  7. Use sane and consistent indentation.
  8. Avoid global variables and side effects in functions (extract probably fails on both counts, but it's not clear from the calling code).
True laziness is hard work

In reply to Re: Sorting array, getting modification of read-only value error by GrandFather
in thread Sorting array, getting modification of read-only value error by myelinviolin

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