in reply to How to store this value in Hash ?

use Data::Dumper;
@ar=([1,1],[1,2],[3,5],[6,7]);

map {test($_->[0],$_->[1])} @ar;

sub test
{
    my ($k,$val)=@_;
    
    if (exists $hash{$k})
    {
        $hash{$k} .= ','.$val ;
    }
    else
    {
        $hash{$k}=$val;
    }
}

print Dumper(\%hash);

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Output: 

$VAR1 = {
          '6' => 7,
          '1' => '1,2',
          '3' => 5
        };

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Re^2: How to store this value in Hash ?
by manav (Scribe) on Mar 21, 2005 at 13:03 UTC
    There's two possible and different ways to do this. 
    push @{$fruits{$a}},$b

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    will create a hash-of-arrays where each hash element references an array. 
    $fruits{$a} .= ','.$b ;

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    will just concatenate all values($b) for a particular key ($a).
    The selection of one of these depends entirely on what is to be done with the hash after it has been populated. For computational purposes, dealing with a hash-of-arrays is (IMHO) easier than doing a series of splits on a value which was constructed by concatenating...
    The hash-of-arrays is easier to iterate through, whereas if you just need to print to output, concatenating might be a better option.

    Manav
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