Can you tell me what my does? Can you tell me the lifespan of @graph?

Taking some advice from Basic debugging checklist lets see what you have so far 

#!/usr/bin/perl --
use strict;
use warnings;
use Data::Dump qw/ dd pp /;
my $string = qq/a b c\nb b c\nd b c\n/;
{
  my @stuff = split '/\s+/', $string;
  dd $string;
  dd \@stuff;
}
__END__
"a b c\nb b c\nd b c\n"
["a b c\nb b c\nd b c\n"]

[download]

So there is 1)problem with your split invocation

If you copy/paste from split documentation or your previous post Regex for non-patterned input a corrected split invocation, you have 

#!/usr/bin/perl --
use strict;
use warnings;
use Data::Dump qw/ dd pp /;
my $string = qq/a b c\nb b c\nd b c\n/;
{
  my @stuff = split /\s+/, $string;
  dd $string;
  dd \@stuff;
}
__END__
"a b c\nb b c\nd b c\n"
["a", "b", "c", "b", "b", "c", "d", "b", "c"]

[download]

Do you see any issues with this? Do you see what your next step should be?

In reply to Re^3: Loading specific columns into arrays by Anonymous Monk
in thread Loading specific columns into arrays by sidsinha

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