evaluating this boolean expression in perl [closed]

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I am trying to do this boolean expression in perl and my code is supposed to be like this

enter code here

开发者_如何学JAVA $flag = 0;
  while (<INFILE>)
{

if(/name/ && $flag==0)
 {
   $flag = 1;

 print "HELLO\n";
 }
elsif($flag)
{
  print "Bye\n";

My plan is to write something like this

flag=0
while<>
if(/name/ && !flag)
flag=1;
elsif(flag)
last;

So is there anything wrong in what i did in the code what i reproduced? Is this the way of declaring a true and false value in perl

---

Based on your comment below:

while (<>) {
    $flag = 1 if /name/;
    if ($flag) {
        # do something
    }
}

Or you can do:

while (<>) { last if /name/ }
while (<>) {
    # do something
}

---

A simple answer is:

In Perl, 0 or '' is considered false. A non-zero number (1, 42, etc) or string of length greater than 0 ( 'true', 'foo' ) is considered true.