c:\@Work\Perl>perl -wMstrict -le
"my @f = (9, 8, 7);
 my $n = scalar @f;
 for (0 .. $n) {
   print qq{index $_: element $f[$_]};
   }
"
index 0: element 9
index 1: element 8
index 2: element 7
Use of uninitialized value in concatenation (.) or string at -e line 1.
index 3: element

##</code><code>##

c:\@Work\Perl>perl -wMstrict -le
"my @f = (9, 8, 7);
 for (0 .. $#f) {
   print qq{index $_: element $f[$_]};
   }
"
index 0: element 9
index 1: element 8
index 2: element 7