foreach my $i (0 .. ($#array/2) - 1) { ... }

This produces an off-by-one error. Either
    ($#array/2)
or the uglier
    (@array/2) - 1
works as I understand the OPer requires.

>perl -wMstrict -le
"my @ra = qw(a A b B c C d D e E);
 for my $i (0 .. ($#ra/2) - 1) {
   print qq{$ra[ $i * 2 ] : $ra[ $i * 2 + 1 ]};
   }
"
a : A
b : B
c : C
d : D

>perl -wMstrict -le
"my @ra = qw(a A b B c C d D e E);
 for my $i (0 .. ($#ra/2)) {
   print qq{$ra[ $i * 2 ] : $ra[ $i * 2 + 1 ]};
   }
"
a : A
b : B
c : C
d : D
e : E
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