I am trying to execute the following line of code : 
#!usr/bin/perl


use strict ;
use warnings ;



my %hash = {'perl' => 1 , 'C' => 0} ;
foreach my $key(sort keys %hash)
{
     print "$key : $hash{$key} \n" ;

        }

[download]
but it gives me the following error : 
Reference found where even-sized list expected at perl.pl line 9.
Use of uninitialized value $hash{"HASH(0x98bf7ec)"} in concatenation (
+.) or string at perl.pl line 12.
HASH(0x98bf7ec) :

[download]
so what is exactly the problem ?

In reply to printing hash produce errors by Xfiles

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