There are a couple ways to fix this problem (at least from where I stand... err... sit ;):

• Exactly who you do it now. Instead of using global array, pass array reference to each subroutine that may require this array or modify it in any way. I have done a similar thing in a couple of my scripts. For example,

  my @data;
  
  foo(\@data);
  bar(\@data);
   
  sub foo {
    my $data_aref = @_;
    # read from a file and
    # save temporary data in the data
    # array
  }
  
  sub bar {
    my $data_aref = @_;
  
    # process data array...
  }
  [download]

• Write a separate subroutine which will do just that: 'find one or more nodes in a binary tree'. Declare your array inside that subroutine (local) and use that array in your subsequent calls that do the actual job of searching the tree.

But seriously, a sample of the code you wrote would help the discussion :).

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# Under Construction
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