in reply to Writing an array inside an array

Please read Markup in the Monastery, and put <code>...</code> tags around your code.

You probably don't want to assing [] to @sub - that way the array doesn't become empty, but holds a single value, which is a reference to an empty array. Use @sub = () instead.

Also you'll probably want $graph[$i] = \@sub (no my before it. You're assigning to a part of an existing data structure, declaring a new variable doesn't make sense in that context).

Also please read perllol, which talks about arrays of array references.

Perl 6 - second systems done right

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Re^2: Writing an array inside an array
by talha099 (Initiate) on Nov 18, 2010 at 13:03 UTC
    Thank you very much!
    Now, it gives me the error saying
    Global symbol "$graph" requires explicit package name
    in the line
     $graph[$i] = \@sub;
    Can you please help me again?
    Thanks very much!
[reply]
[d/l]

      try using 

      my @graph = ();

      [download]
      when you initialize the variable at the top of your code. Think of it as a declaration. You should NOT use 'my' again on the variable however.

      HtH

      Misha/Michael - Russian student, grognard, bemused observer of humanity and self professed programmer with delusions of relevance
[reply]
[d/l]
        Yeah, it still gives me the error
        "Global symbol "$graph" requires explicit package name at line 39".
        The code which I have is 
        
use strict;
use Graph::Matching;

use Graph::Matching qw(max_weight_matching);

my @sub = [];
my @list = split(',', $ARGV[0]);

#print("@list");

my $n = 0;
my @graph = ();
my $i = 0;
my $j = 0;

for ($i=0; $n<my $graph; $i++)
{
 for ($j=0; $j<=2; $j++)
  {
   $sub[$j] = $list[$n];
   $n++;
  }
 $graph[$i] = \@sub;
@sub = ();
}

        [download]

        Thank very much again!
[reply]
[d/l]
[reply]
[d/l]

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