On Fri, Mar 27, 2009 at 11:20:27AM +0000, Dermot wrote:
> Hi All,
<snip> 
>                   $bits |= 1<< ($countryid - $currentno);                 ### 
> What
> is this left shift doing? Is that a or complement?
>               }
>               else
>               {
>                   $bits &= 15- (1<< ($countryid - $currentno));      ### ditto
>               }

When trying to understand someone elses code I find little tests
like this helpful, perhaps you will too.

    perl -le '$bits=0xffff; for $i ( 0 .. 15 ) { 
        printf "%016b\n", $bits &= 0xffff - 1<< $i;
    }'
and
    perl -le '$bits=0; for $i ( 0 .. 15 ) { 
    printf "%016b\n", $bits |= 1<< $i;
    }'

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