Shell Programming and Scripting

$str="orange AND grapes NOT pineapple";

$str="orange AND grapes NOT pineapple AND papaya";

$str="orange AND grapes NOT pineapple AND jackfruit NOT "fruit juice"";

while($str=~/\sNOT\s([^()]+)/g)
{
        print "<br>entered<br>";
        print "<br>**********$1<br>";
}

orange AND grapes
orange AND grapes AND papaya
orange AND grapes AND jackfruit

@arr = ("orange AND grapes NOT pineapple",
        "orange AND grapes NOT pineapple AND papaya",
        "orange AND grapes NOT pineapple AND jackfruit NOT fruit juice");

for $str (@arr) {
    print $str, "\n";
}
print "\n\n";

for $str (@arr) {
    $str =~ s/\sNOT [\sa-z]+(\z|( AND))/\1/g;
    print $str, "\n";
}

$str=~s/NOT ("[^"]*"\s*|\w+\s*)//g;