If i have data of format

name, amount

john, 100

john, 200

barry, 300

barry 200

how would i represent this data so i could iterate over the names and add the values so i would get output

john, 300

barry, 500

I have written code which will see if the names occur more than once but i can't work out how to sum the values for the names that appear more than once. I am very new to perl and know that a hash is required but hashes seem incompatible with my brain. I would appreciate it if someone could help with a simple explanation. 

my %seen ;
open(DATA, "<", "names.txt") or die "cannot open names.txt" ;

while (<DATA>) {
$line = $_ ;
@array = split(/,/ , $line ) ;
$name = $array[0] ;
$amount = $array[1];

$seen{$name}++;

 if ( $seen{$name} > 1 ) { 
                                     print "$name occurs more than onc
+e" ;
                                    }

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In reply to adding values of element by new2perl2

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