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Beginner's Tutorial for CGI using Perl Language
While

While loop

Now we arrive at the while loop. A loop not to be taken lightly. If you ever see your program perpetually executing something, a while loop is most likely the culprit. I have lost count how many times I have stared at the screen when it was scrolling lines and lines of data endlessly forever when only a couple of times was necessary. You guessed it - a badly written while loop.

Syntax
while ( condition ) {
body
}

Execute script repeatedly as long as a given condition is true. OK! Here comes the example...

#!/usr/local/bin/perl

print "Top 10 Surprises in Windows 2000\n\n";
#Make a list of surprises
my @surprises = ( "You get $10 off if you voluntarily give them your soul, 
	but it's full price if they have to force it out of you.",
"It is still possible to fix a sandwich and something to drink while 
	waiting for Start Up.",
"When you peel off the label on the CD, there's Window'95 label under it.",
"To open Netscape : Press ctrl d, alt 4, tab, tab, spell Nebraska backwards 
	and press enter, enter your gender, compose a 500-word essay.... ",
"Entering \"Department of Justice\" into Organization Field during set-up 
	will crash system" ,
"New app monitors Bill Gates's wealth for you to see" ,
"Mix-up in shipping department sends a dog named \"Bowser\" with every copy" ,
"A \$1 off coupon for Mrs Smith's cream pie with Bill's home address on back" ,
"Includes sample bugs from upcoming Windows 2000 Advanced Server!" ,
"Surgeon General has put a warning on Solitaire that repeated use may be 
	habit forming.");

my $no=10;
while ($no > 0) {
	print "Surprise $no : $surprises[$no-1]\n";
	$no = $no - 1;
}
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