Here is a really simple solution that will not use too much memory. 
use strict;

use vars qw (%data);

open(KEYS, "keys.txt") or die "error: keys.txt $!";
open(VALS, "values.txt") or die "error: values.txt $!";

while (my $key = readline(*KEYS)) {
    my $val = readline(*VALS);
    chomp $key;
    chomp $val;

    print "$key = $val\n";
    unless (exists $data{$key}) {
        $data{$key}{min} = $data{$key}{max} = $data{$key}{total} = $va
+l;
        $data{$key}{count} = 1;
    } else {
        $data{$key}{min} = $val if $data{$key}{min} > $val;
        $data{$key}{max} = $val if $data{$key}{max} < $val;
        $data{$key}{total} += $val;
        $data{$key}{count}++;
    }
}

use Data::Dumper;
print Dumper \%data;

[download]
-- gam3
A picture is worth a thousand words, but takes 200K.

In reply to Re: Summing repeated counts for items stored in separate file by gam3
in thread Summing repeated counts for items stored in separate file by dmorgo

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