But note also:

c:\@Work\Perl\monks>perl -wMstrict -le
"sub get_max_index {
 my $imax = 0;
 foreach (@_)
 {
     $imax = ($0 .. !$0) if $_ > $_[$imax];    print 'imax ', $imax;
 }
 return $imax;
 }
 my @arr = (1,2,13,4,5, 99);
 my $ans = get_max_index(@arr);
 print $ans;
"
imax 0
imax 1
imax 2
imax 2
imax 2
imax 3
3
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