Hi,

I've just started using hash tables and could use some help with something. I need to whip through two hash tables and provide the following kind of summary:

1) elements common between two tables
2) elements unique to table #1
3) elements unique to table #2

Is there any way to do this with one pass through both hash tables, or do I pretty much have to pass through each hash table once?

Here's what I'm doing:-
%astpd = ();
%astslack = ();

$ln = 0;
while ($in1s[$ln] ne "") {
        chop ($in1s[$ln]);
        @in1saa = split(/\s+/,$in1s[$ln]);
        $aststartend = join (" ",$in1saa[0],$in1saa[1]);
        $astpd{$aststartend} = $in1saa[2];
        $astslack{$aststartend} = $in1saa[3];
        undef (@in1saa);
        $ln++;
}

%ptpd = ();
%ptslack = ();

$ln = 0;
while ($in2s[$ln] ne "") {
        chop ($in2s[$ln]);
        @in2saa = split(/\s+/,$in2s[$ln]);
        $ptstartend = join (" ",$in2saa[0],$in2saa[1]);
        $ptpd{$ptstartend} = $in2saa[2];
        $ptslack{$ptstartend} = $in2saa[3];
        undef (@in2saa);
        $ln++;
}

[download]
Any suggestions on the *fastest* way to meet my 3 criteria above? (The keys to match are $aststartend and $ptstartend. Once a match is made, write $astpd, $ptpd, $astslack, and $ptslack to a file...)

Many thanks in advance...

update (broquaint): added <code> tags

In reply to Hash table question by fiddler42

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