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Re: Display last record

by davidrw (Prior)
on Dec 31, 2005 at 17:35 UTC ( [id://520172]=note: print w/replies, xml ) Need Help??


in reply to Display last record

There's no need for a temporary array when doing:
@reverse = reverse @data; @data = @reverse;
You can just do: @data = reverse @data and then print $data[0];. But to get the last item, you don't need to reverse the list -- just use the $#data or -1 index .. these are all the same:
print $data[-1]; print $data[$#data]; print pop @data; # NOTE: THIS SHORTENS THE ARRAY print scalar splice(@data,-1); # NOTE: SAME AS pop # or: @data = reverse @data; # OF COURSE, @data IS NOW MODIFIED print $data[0]; print shift @data; # NOTE: THIS SHORTENS THE ARRAY print scalar splice(@data,0,1); # NOTE: SAME AS shift


All of that is assuming you read your whole file into an array in memory, which is obviously costly for memory if the file is large ... A quick search revealed Read Last Line of A File Only

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Re^2: Display last record
by ikegami (Patriarch) on Dec 31, 2005 at 21:17 UTC
    Don't forget @data can be eliminated totally with (<DATABASE>)[-1]. It still loads the whole file into memory, though.

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