my $j = 0; # file/column number
foreach $file (@files){
    open(INP,"$file") or die "Cannot open file :$!\n";
    while (<INP>){
        chomp;
        my($key,$value) = split "\t";
        if(exists $trans{$key}){
            $trans{$key}[$j] = $value;
        }
    }
    close(INP);
    $j++;
}