Perhaps this

$ perl -le '
> vec($str, $_, 1) = 1 for 1, 8, 9;
> $high = unpack q{xc}, $str;
> $low = unpack q{c}, $str;
> print qq{$high - $low};'
3 - 2
$

[download]

Cheers,

JohnGG

In reply to Re: Making two 8-bit numbers from indices of set bits by johngg
in thread Making two 8-bit numbers from indices of set bits by carcassonne

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