in reply to Re^3: Efficient array element deletion
in thread Efficient array element deletion

I thought you were referring to the off-by-one error, and didn't notice it also iterated backwards.

Solutions:
for ( -$#array..0 ) { ... $array[-$_] ... }
for ( my $i=@array; $i--; ) { ... $array[$i] ... }

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Re^5: Efficient array element deletion
by BrowserUk (Patriarch) on Dec 05, 2008 at 14:11 UTC

    Here's another approach to accessing the elements of an array in reverse order without creating a list: 

     @a = 1 .. 9;;

print "$_ : -$_ :  $a[ -$_ ]" for 1 .. @a;;
1 : -1 :  9
2 : -2 :  8
3 : -3 :  7
4 : -4 :  6
5 : -5 :  5
6 : -6 :  4
7 : -7 :  3
8 : -8 :  2
9 : -9 :  1

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[d/l]
      This is actually what I meant to do originally, I just didn't quite understand how negative indices were interpreted.
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