for ($i = 1; $i < 5; $i++){
$a[$i]{'name'} = "file$i";
open IN, "<file$i" or die $!;
while(<IN>){
        if (/(\w)\t(\w)\t([\d\.]+)/){
                $a[$i]{"$1$2"} = $3;
                $a[$i]{'total'} = sprintf('%.2f', $a[$i]{'total'}+=$3);
        }
}
close(IN);
}

foreach $key ('name', grep {$_ ne 'name'} sort keys $a[1]){
        print join "\t", $key, map($_->{$key}, @a[1..4]),"\n";
}