in reply to Re^2: suppress the elements that appear more than one time in a list
in thread suppress the elements that appear more than one time in a list

It would perhaps be better from a maintenance point of view to leave the line

$Hash{$k} += $v;

as it is and change the split to reflect the fact that your value comes before the key on the line

my ($v, $k) = split /;/;

You still need to use += since you wish to accumulate the values.

Cheers,

JohnGG