Your $hit variable is undefined if your $orth variable doesn't match /^A(\d+)/. You might want to check for that.

Also, you seem to come from a C-like programming language. The loop could be written in a shorter, less error-prone way as

  push @hits, grep {/$hit/} @pids;
  push @potential_hgt, grep {! /$hit/} @pids;

[download]

There also is a module which implements the part function, which divides one list into two (or more) lists, which would be quite handy here, but I don't find that module at the moment.

In reply to Re: for loop trouble by Corion
in thread for loop trouble by Anonymous Monk

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