help in if - else loop in perl

[Sayed, Irfan (Irfan)]

Hi All,
 
I am getting error while running following script.Error is due to
improper if else loop and curly braces.
 
Can you please guide me in placing the braces in right position and
doing proper if..else looping

My requirement is that I want to quit as soon as "if condition"
fails.Please guide

if ($menu_item == 1) (if this condition fails then i want to quit)
         {
$pvob=`$CT lsvob -s | grep apc`;
chomp($pvob);
my @proj=`$CT lsproj -invob $pvob | cut -d " " -f3`;
[EMAIL PROTECTED];
print "The projects are.....\n\n";
my $i=1;
foreach my $line(@proj)
{
 print "\t" . $i++ . ". $line\n";
  }
print "Your Choice :\t";
chomp($choice = <STDIN>);
if ($choice < $len){ (if this condition fails then i want to quit)
print "Your choice: $proj[$choice-1]\n";
chomp($pro=$proj[$choice-1]);
 chomp($proj1=$pro . "@" . $pvob);
 #print "$proj1\n";

      my $int_str=`$CT desc -fmt "%[istream]p" project:$proj1`;}
     else {quit();}
     elsif ($int_str eq "") { print "This project does not have
Integration stream , so quiting.....\n"; exit; }(if this condition fails
then i want to go to following else loop)
     else{
      print "Integration Stream:$int_str\n";
      dev_strm();}

}
else {quit();}

Regards
Irfan