$str="old and restless";
print "$&\n" if $str =~ /and/;
print "$'\n" if $str =~ /and/;
print "$'\n" if $str =~ /and/;
print "\nold string is: $str\n";
$str=~s/(old) and (restless)/$2 and $1/;
print "new string is: $str\n";
print "\nlast pattern matched: $+\n";