[19:51:25.70] C:\test>\perl64-16\bin\perl \perl64\bin\p1.pl
[0] Perl> say $];;
5.016001
[0] Perl> $s = 'fred'; $s x= 1024**3;;
[0] Perl> ++$n while $s =~ /fred/g; say $n;;
Use of uninitialized value $n in say at (eval 9) line 1, <STDIN> line 3.

[0] Perl> $s = 'fr'; $s x= 1024**3;;
[0] Perl> ++$n while $s =~ /fr/g; say $n;;
Use of uninitialized value $n in say at (eval 11) line 1, <STDIN> line 5.

[0] Perl> $s = 'fr'; $s x= 1020**3;;
[0] Perl> ++$n while $s =~ /fr/g; say $n;;
1061208000
[0] Perl>