use strict;
my $str = '+33611223344+33611223344
0611223344 0744332211
0744332211+33611223344
0744332211 +33611223344
0611223344
0744332211
+33611223344
+33744332211
06112233440744332211';
my $regex = qr/^(\+\b33|\b0)[67][0-9]{8}$/mp;
my $subst = '';
my $result = $str =~ s/$regex/$subst/rg;
print "The result of the substitution is' $result\n";
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html