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in reply to Re^2: split every other value
in thread split every other value

I shouldn't have used the names "@odd" and "@even", seeing as how we're supposed to be dealing with text. So here's a program which doesn't use those terribly misleading names, and deals with undefs.

#!/usr/bin/perl use strict; use warnings; my @array = map{chr} ('32' .. '126'); push @array, undef, undef; unshift @array, undef, undef, undef; # split elements into two arrays my (@arr0, @arr1); while (@array > 1) { my ($el0, $el1) = splice @array, 0, 2; push @arr0, $el0; push @arr1, $el1; } # get the last element if there is one if(@array) { push @arr0, shift @array; } # check that all elements were gotten die "still elements left" if (@array); print "arr0 = @arr0\narr1 = @arr1\n"; __END__

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Re^4: split every other value
by Aristotle (Chancellor) on Aug 07, 2004 at 01:34 UTC

    If you do away with the conditionals like that, the temporaries in the while loop are superfluous.

    my ( @arr0, @arr1 ); while( @array > 1 ) { push @arr0, shift @array; push @arr1, shift @array; } push @arr0, shift @array if @array;

    Or you could pull the conditional back into the loop:

    my ( @arr0, @arr1 ); while( @array ) { push @arr0, shift @array; push @arr1, shift @array if @array; }

    Makeshifts last the longest.

      Yep looks good to me.